Factors Affecting Semen Production

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A statistics project takes Kara way past her comfort zone.
3.6k words
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Part 1 of the 3 part series

Updated 03/05/2024
Created 01/26/2024
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'How's it going?' she asked through the door.

'It's fine,' he said.

She waited. When he didn't say anything else, she called, 'Um, how much longer...I mean, do you think you...it...will be done soon?'

As soon as she said the words, she realized how bad it sounded. 'I'm not trying to rush you or anything, just to get a sense...'

Kara was blushing even though Matt couldn't see her. Somehow she had ended up waiting by her bathroom door for a boy to bring her his semen. It was not how she had envisioned the semester going.

It was her sophomore year at university. She was a quiet girl, not one of the people who found it easy to be at parties, which is what everyone else seemed to be doing pretty much all the time (her roommate, Octavia, certainly went to a lot of parties). She mostly went to classes and studied and worked at one of the libraries on campus.

So how did she end up talking to a boy while he masturbated in her bathroom?

It all started with her stupid health statistics class. Everyone joked about it when Professor Clinton handed out the list of topics for their semester-long research project. Kara even laughed a little, but she certainly didn't expect to end up with the topic herself. But then her bike chain broke on the way into class and by the time she got there, it was the only topic left on the board that didn't have a name next to it: factors affecting semen production.

There was a lot snickering and giggling at the end of class when Professor Clinton added her name to the board with a perfunctory, 'So now you all have your research assignments for the semester.' Kara made a beeline for the door and vacated the building as quickly as she could. She had no desire to field snide questions about her methodology.

She raced home in a blur and and slammed the door shut as she came in, bringing her roommate round like a curious pigeon.

'Hey, what's up with you? Somebody invite you to a party?'

'Homework,' said Kara hoping to avoid talking about the matter.

'Homework doesn't usually make you angry,' said Octavia. 'What's the assignment, that you have talk to a cute boy?'

'Not exactly,' said Kara. She knew that Octavia wasn't going to let it go, so she gave in and told her about the research project.

For once, Octavia didn't make a joke. 'Wow,' she said.

'How am I even going to find someone to produce the semen!' Kara was so frustrated at this point, she had lost her characteristic shyness about all things sexual. Octavia was much less decorous about such matters.

'What's the big deal?' she said. 'It's not like you have to do it for them. Besides, maybe you can find someone cute to experiment on.'

'I'm not experimenting on anybody!'

'It's not that big of a deal,' said Octavia. 'It's a very human thing. Fifty percent of the population ejaculates. You're just inexperienced. Do you even know what semen looks like?'

Kara didn't think of herself as inexperienced, just she hadn't ever seen a man's penis except in pictures and she certainly hadn't ever seen an erect one. As far as ejaculation, well, she understood the concept, but this was definitely going to be the first time she had seen semen in real life.

'What about a penis? Have you ever seen a man's penis?'

'In a picture,' said Kara.

'I knew you were sneaking porn on me!' shouted Octavia.

'It was not porn!' said Kara. 'I think it was in a textbook or something.'

'I'm definitely taking all the wrong classes, because you're getting research projects on masturbation and textbooks with pictures of cocks in them.'

'What am I going to do?,' Kara groaned. 'Just walk up to a boy and say, 'Hi, I'm doing a science project, can you masturbate for me?''

'You could try that. You're pretty cute. I bet you'd could get half the guys on campus to say yes, but you probably want to choose your target carefully.'

'What do you mean?'

'Don't ask some creepy old guy. Also don't ask a jerk. Honestly, maybe you should have me around for backup.'

'You just want to see someone masturbate.

'I won't deny the situation has a contains a certain level of titillation, but honestly, Kara, I'm saying this for your own protection.'

Talking with Octavia didn't help Kara feel better about the situation. She decided to ignore the problem for the rest of the day. But she wasn't the kind of person who could put things off. After half an hour, she had come to the conclusion that there really was nothing for it but to find a boy and ask him to produce some semen.

She decided that it should be someone she didn't know, because after this semester she was probably going to be too embarrassed to ever talk to them again. But when she went through all the boys she knew of but didn't know, she simply couldn't imagine asking any of them.

By evening, Kara was completely miserable. Feeling lonely and not knowing what to do with herself, she went to a cafe near campus. It was one of those coffee shops that lurk near colleges and serve coffee late into the night. Because it was Friday, she was the only customer except for some old man with a beard and a lot of bags hanging out at a table in the back.

She ordered an espresso from the young guy behind the counter. She knew him a little, at least, she had seen him work this shift a lot, and they sometimes exchanged pleasantries. He was always wearing a t-shirt with a band from the '80s on it. She wasn't sure if he was a student or not; in fact, she realized, she didn't even know his name.

She remarked how quiet it was, and he said yeah, but it was a Friday night, and in a flash she decided she was going to ask him.

'Can I ask you to help me with something?' she said, and her heart was suddenly beating like it was going to break her rib cage. 'I'm trying to measure factors that affect...um...I don't know how to say this, so I'm just going to go for it: I'm trying to measure factors that affect semen production and I need a boy to uh, well, to produce semen.'

She had been dreading saying it so much that she hadn't really thought about what came next.

'I...' was all he said. 'I don't think I understand.'

'Well, I'm supposed to measure how different things affect semen production, and, you know, being a girl, I don't really have a way to do that myself. So I...I thought you might be interested.'

He didn't say anything.

'I don't mean you are interested in semen production specifically, not that you aren't interested in it--just that if I asked, you might be willing...'

At this point she was so uncomfortable she was ready to abandon the whole thing, including her coffee and run out of the cafe. It must have been clear to the boy as well, because he finally found his voice and said, 'Sure...yeah.' He said it more to make her feel better than because he realized what he was saying.

'You would?' she said, almost shocked. She had felt the conversation was going so poorly that she couldn't keep the surprise out of her voice.

'Uh, yeah, I guess. What do you need me to do?'

'Well, we have to get a baseline first, so maybe we can start this week, and I need to time you as well because I want to track how long it takes in case there's a connection there.'

'Time me...?'

'From when you start.'

'Start...you mean...'

'Masturbating,' she said, having got so caught up in the details that she forgot how awkward it was.

'Ah,' he said.

She looked at his face, for maybe the first time in the whole conversation and it was clear that what she wanted was finally dawning on him.

'You want me to...while you watch?'

'What? No!' she almost shrieked.

'Right, of course not.'

'No, no. I just need to time you and weigh it afterward.'

'So you want me to masturbate into a cup or something...and you're going to time me?'

'Look, I know it sounds crazy, but it was the only subject left and I really need to do well on this. Please?'

She was afraid he was going to back out now, and she definitely wasn't going to go through asking someone again.

'Okay,' he said. 'How are we going to do it?'

She explained that he could come over to her apartment and use the bathroom. She had thought about this for a long time: inviting him to her place made it feel significantly more intimate, but she reasoned that it was better than feeling nervous about getting caught if they tried to use a public bathroom somewhere. She gave him her address and he agreed to come over on Monday morning. She was so nervous she left without even touching her espresso which had grown cold while they talked.

When she got home, she realized she hadn't asked his name. In fact, it occurred to her that it was possible he didn't know hers. What if he didn't come? What if he couldn't manage to do it? What if he tried to come on to her? Of course he wouldn't do that. He seemed like a really nice boy. Octavia had just scared her with her safety talk.

She barely slept that night and the next morning she was so anxious that Octavia stopped asking questions about the research project entirely. It felt like the longest weekend of Kara's life. And her hands were horribly clammy Monday morning as she waited for him to show up. He was a few minutes early.

'Morning,' he said when she opened the door.

'Hi,' she said.

'I wasn't sure if there would be anyone here...I mean, I kinda thought you were putting me on. Like a practical joke.'

'That would be an awful joke,' she said. 'Um...you should come in.'

They stood in her apartment in silence for a moment, until Kara burst out:

'This is great! Thank you so much! You wouldn't believe how I worried I was about this project. There's just a few questions I need to ask, and um, well...when I was writing them it didn't seem like they were that...uh, well they just were easier to write...'

'Just go for it,' he said. 'It's not a big deal.'

'Okay, well, I need to know how often you ejaculate.'

'Oh,' he said, perhaps caught a little off guard by the first question.

'I need to know what the baseline is so we can

'Every day,' he said, somewhat quietly, as if he had decided to be frank about things and he was going to go down with the ship.

'Every day?' It was Kara's turn to be surprised. She had heard the boys had a lot of sex drive, but every day certainly seemed like a lot. She wondered if he got sores or if it got chaffed from all the rubbing.

'Is it usually around the same time of day, or just whenever you're...you know?'

'Usually at night. Sometimes in the morning.'

'And do you...how do you get aroused?'

'Porn, usually. Sometimes I just am.'

'How long does it take?'

'Not very long. I don't know, a few minutes, maybe ten.'

'Do you need to watch porn or something? I've heard that a lot of guys do that but maybe you can just you know...do it?'

'I think I can probably do it. Honestly, I think I'll be too embarrassed having you be out there knowing I'm watching porn. I don't think it would be very arousing.'

'Are you going to be able to ejaculate?'

'I think so. I've never done it will somebody waited.'

'Okay, well, maybe you should just give it a shot and we'll see how it goes?'

'Yeah, that sounds good.'

'You can use the bathroom,' she said.

'Of course, yes. I'll just go and...'

He got up and went into her bathroom, shutting the door behind him. She heard him lock the door, and then after a brief pause, unlock it. And then it was just silent.

Kara waited for what felt like a very long time, but when she checked her phone it had only been two minutes. So she decided to wait, she didn't want to rush him.

After a few more minutes, she began to hear a wet sound, kind of rhythmic and sticky. She wondered if he had already ejaculated.

'How's it going?' she asked.

'Fine,' he said in a funny clipped little voice.

When he didn't say anything more, she asked, 'Um, how much longer...I mean do you think you are close?'

She could hear him breathing heavily and then she heard him make a low, sighing kind of sound.

'Was that...are you done? I need to stop the timer if you are.'

'Yes,' he said in a kind of creaky voice. She heard him washing and then the clinking of his belt buckle and his pants zipper. The door opened and he came out, sheepishly holding the plastic sample cup.

'Here you go,' he said.

The sample cup was not quite half-filled with a pearly white liquid.

'That's all?' she asked.

'That's it,' he said, a little offended.

'Oh no, not that...it's...it's just I thought there would be more. I've never actually seen...I mean I didn't know what to expect.'

Kara took the sample cup from him and put it on her scale. She noted the mass and straightened back up.

'Well, uh, thank you! This really is a big help.'

'Um...sure.'

There was an awkward pause where neither of them knew what to say. Kara offered the cup back to him.

'Do you want this back?'

'No,' he said with a slight frown. He made his way to the door and as he was leaving he stopped and said, 'I'm Matt, by the way.'

'Oh! I'm Kara.

'I'll see you tomorrow Kara.'

Overall, Kara felt that it had gone rather better than she expected. It really wasn't that awkward, considering that she had actually invited a stranger to orgasm in her bathroom.

The next time it didn't take Matt nearly as long, in fact she was a little startled by how fast it happened. Wednesday was the same: Matt knocked on the door, they chatted a little and he went into the bathroom and came out rather quickly with a sample cup half-filled with semen.

And then came Thursday.

Matt was late. Kara was surprised as he usually was waiting for her in the hallway when she got there. But now it was ten minutes past and he still hadn't shown up. She thought about calling him, but realized she didn't even have his number.

Just as she was about to give up and leave for class, she heard loud footsteps running up the stairs. Matt burst out of the stairwell, out of breath.

'Sorry I'm late,' he gasped.

'Oh no! What happened to your hand?'

His left hand was covered in plaster cast up to his forearm.

'I was climbing something and fell and broke my wrist,' he said.

'Are you still going to be able to masturbate?' she asked, and of course it was just the kind of comment she made when she was nervous: practical to a fault and unthinking. She immediately followed it up with 'Are you going to be okay?' before he could answer the first question.

'I should be fine. I still have one free hand,' he said, and took the sample cup from her. He turned to open the bathroom door but couldn't with his broken wrist, so he fumbled for a minute and tried to pass the cup to the hand with the cast and promptly dropped it.

'Are you sure you can do this?' she asked.

Kara had a good set of data and she didn't want to ruin it because he dropped the sample cup and spilled everything. How could he have been so stupid? In her mind she knew that her project wasn't his most important priority, probably wasn't even high on the list, but still-climbing a building!

'What else can I do?' he said. 'I'll manage.'

He was about to step into the bathroom when Kara said, 'Wait!'

She wasn't going to let a little squeamishness ruin her project.

'I'll hold it for you,' she blurted.

'I've already got it,' he said, thinking she meant the door.

'I'll hold the sample cup,' she said. 'I don't want this messed up.'

Matt looked startled. She realized she needed to say something else.

'It's not a big deal,' she said, but he still looked startled and so she added, 'I can close my eyes or something.'

'No,' he said, with an odd tone. 'I mean, it's okay.'

She realized that he was too polite or shy to take the lead, so she said, 'Come on,' and walked into the bathroom.

He followed her but still seemed reluctant.

'Okay, um, well, let's get started.'

Matt looked sheepish for a moment, but slowly unbuckled his belt and undid the button on his jeans.

'Are you sure the door is locked?'

'Yes,' she said, with some exasperation. Now that she had decided to do it, she really didn't see what the big deal was.

'Come on, I've got class in half an hour.'

He slowly unzipped, but then stopped. He seemed to be struck with stage fright.

'It's okay,' she said. 'It's not a big deal. You're just going to take out your...your penis and do whatever...uh...do what you do and that's it. Humans have been doing it for thousands of years.'

'Okay,' he said, voice slightly shaky.

He reached into his pants and pulled out his penis over the waistband of his boxers.

He was clearly very aroused. It was rigid and there was a large droplet of something clear coming out of the slit in the tip.

They were both silent, staring at his penis. While they stared the clear droplet slowly fell to the floor, leaving a long thread hanging from the head of his penis.

'Oh, she said. 'You didn't already...did you...in your pants, I mean.'

'What? No!' Matt exclaimed. 'That just happens when I'm...before I start...' he trailed off.

'Oh, good,' she said.

There was another pause.

'Well, I better...'

'Yeah,' she nodded, still looking at his penis.

'I'll let you know when I'm close and you can kinda hold the cup under the tip.'

'Like this?' she asked, moving the cup to an inch or two below the head of his penis.

'Yeah, but closer, and you might need to tilt it up a bit. Sometimes it shoots out a ways.'

He started stroking himself. His good hand was wrapped around the shaft of his penis, moving up and down. His penis was now clearly erect. The head was almost purple. It looked painful. He stopped for a moment and reached into his pants to push his waistband under his balls. They bulged out to the side when he went back to stroking.

He was going faster now, but again he paused. This time, he used one of his fingers to catch a large bead of clear fluid from the tip of his penis. he rubbed the wetness all over his shaft and head of his penis. He stroked a few more times and paused to catch more of the fluid hanging from the tip. This time he mostly rubbed it over the head. Apparently it was sensitive because he flinched as he did this.

Until now, Kara had been so caught up in watching him, that she hadn't at all thought about how intimate it was.

Her eyes snapped up to his face. He was watching her intently while he masturbated. Their eyes met for a moment.

'I think I'm gonna...you know...'

'Huh?'

'I'm going off!' he said in a strained voice, turning his penis toward her.

'Oh!' she exclaimed and brought the cup up and he pushed the head of his penis into it. Thick, white spurts of semen hit the bottom of the cup with enough force she could feel it. he continued to stroke himself and Kara watched as more spurts of the stuff came out of the slit in the end of his penis. There was considerably more than any of the previous times. In fact the cup was almost overflowing.

'I think I'm done,' he said. His voice still slightly odd. She moved the sample cup away from his penis, but noticed that a sizable glob of semen was still hanging from him.

'I think I need to get that...' she said.

'What?'

'There's still some...on your...'

'What?' Oh,' he said, and tilted his penis up so he could see. 'Oh yeah, um...'

'Here, I'll just...' she tried to catch it with the lip of the cup, but the angle wasn't right, and the cup was so full she was afraid it would spill if she tipped it. And then before she knew what she was doing, she had grabbed the shaft of his penis with her other hand and neatly wicked the bit of semen off the tip with the cup.

He gasped and she immediately let go.

'Sorry, I didn't mean to. I mean, I just wanted...uh, I needed to get that,' she said, somewhat lamely.

They were both unsettled by the whole experience. It was more than either of them had expected. And he put himself back together in silence while she put the cup on the scale and recorded her measurements.

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