Diary Of a Lactoholic

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A sister becomes addicted to her sisters milk.
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Warning contains: breast expansion, hyper breast expansion, belly expansion, hyper belly expansion, lactation, hyper lactation, incest, nipple penetration.

September 8, 2018

Dear Diary,

This is just the worst. My lazy, annoying sister is moving in with me next week. Mom and Dad called me and asked me to look after her. They're always taking her side. I said no at first, but Mom and Dad wouldn't let up till I finally caved. Can you believe this bullshit? How is it when I'm the younger sister I have to bail out my older sister? I mean she's twenty-six she should be able to take care of herself by now.

I'm only nineteen and I've got a successful blog that generates enough income to keep me going. I'm also a freelance writer along with that and, and I'm also working on my novel during my downtime. I do all of that and still, Mom and Dad expect me to babysit Nicky. That fat ass hasn't done a hard day's work in her life. I just know she's going to freeload around my place driving me crazy.

Marua

September 15, 2018

Dear Diary,

Okay, so we got my sister all moved in today. It was actually kinda a fun day. I haven't seen Mom and Dad in a while so spending the day with them was nice. Once we got Nicky all moved in, with no help from Nicky I might add, we went out to supper. Thai food is the best! I swear I could just eat and eat and eat it till my belly was bigger than me. Oh that reminds me, I have some freelance stuff I need to work on later. Gotta make that dolla dolla bill girl!

Marua

September 18, 2018

Dear Diary,

Well, Nicky has been here a couple of days now and things have been going pretty well. We've been watching a few things together, cooking, talking boys, you know the usual sister stuff. The company has actually been kinda nice. I haven't had a roommate in a long time, so having someone else to talk to on occasion does make things less lonely.

Of course, Nicky still hasn't unpacked everything yet. She keeps reassuring me she's gonna get to it real soon. I hope so, I've only seen her wear sweaters and jogging pants since she's moved in. Not for nothing, but I'll agree with Jake the dog sweatpants are basically give-up-on-life-pants.

Marua

September 22, 2018

Dear Diary,

I'm pretty sure Nicky only owns seaters and jogging pants. It's been over a week and she has yet to wear anything different. It's so lazy! I mean have some pride in yourself, how are you supposed to get a job if you keep going everywhere looking like you just woke up. Not to mention she drank the last of the milk and just put the empty container back into the fridge. Who does that!?

In some good news, I managed to finish up some of my freelance commission work. Which is good since I need the extra cash since Nicky keeps eating me out of house and home. Though to be fair Mom and Dad sent me out some money to help pay for food. Why do they just let her leech of them like that? They were constantly grilling me to get my education and get a job. Why does Nicky get a free pass!? Ugh it's just so annoying.

Marua

September 28, 2018

Dear Diary,

It's almost been two weeks since Nicky moved in and she still dresses like a slob. I would say it's to cover up the fact that she got fat or something, but given how often she just roams around in her underwear I know that's not true. The only thing fat about Nicky is her ass which she never fails to flaunt at me. Plus, there are clothes all over the apartment now, god! How can she be so untidy? If she doesn't start pulling her weight I'm going to have to kick her out. I'm not suffering my sanity because she's too lazy to work.

Marua

October 5, 2018

Dear Diary,

I told Nicky that if she soon doesn't start actually trying to find work I'm calling Mom and Dad to come get her. She can freeload off of them for a change. I know she likes it here and doesn't want to leave so hopefully that means she might actually take this seriously and give an honest effort in trying. I know it seems a little harsh but she's heading for thirty she's got to grow up sometime.

On a positive note, commissions are coming along well. I swear I'm getting more and more popular as a writer. People really seem to like my style of writing I guess. Either way, I'm just happy I get to express myself in the community that I love.

Marua

October 6, 2018

Dear Diary,

That bitch! That manipulative bitch! She went snooping through my computer and copied a bunch of stuff from my private files. Now she's threatening to tell Mom and Dad what I do for money if I don't let her stay. Stupid, stupid, stupid! Why didn't I have a password on my computer!? Now Nicky knows I'm into breast and belly expansion, she knows what a weirdo I am.

I don't know what to do. I can't have Mom and Dad find out that their daughter, the one who's supposed to have it put together, makes her living off of writing smut. Shiiiiiiiit! Damn it! I can't believe she would do this to me. Nicky, I can't believe she did this. Well, lesson learned at the very least. I have passwords on everything now.

Marua

October 9, 2018

Dear Diary,

Great Nicky's new favorite game is to taunt me about my fetish. For two days now she's been stuffing stuff under her sweater to make it look like she has big boobs or a big belly. "Help me Marua I'm blowing up," she's always saying. Why does she have to be so mean? Everyone has something they're into. I doubt she's any different. I'd like to try and get her back, but the only thing she carries on her is her cellphone. That's permanently attached to her at all times. There's not much I can do now I guess I'll just have to put up with it.

Marua

October 13, 2018

Dear Diary,

I think Nicky saw me crying the other day. She apologized for being so mean, she said she would stop teasing me. Hell, she even cleaned up a little so she must have felt really bad. Weirder still, she asked me what I would think if she could actually grow her boobs bigger. I told her I'd let her live here for free if she could grow her boobs bigger, like that'll ever happen.

She said she was going to stop teasing me, then she asked that. She's got a weird way of keeping her word. Though you know, even though it was kind of annoying when she would stuff her top, it was also kinda hot. Well, it would have been if she wasn't my sister. Maybe stuffing my top some time could be fun.

Marua

October 15, 2018

Dear Diary,

Nicky showed me some pills today. She said they were lactation inducers. Apparently, she got them from a friend who knew some doctors working on some stuff not available to the public yet. Like Nicky would know anyone like that. I told her to leave the weird fiction to me. She said she would prove it and took two of the pills right there in front of me. I don't think I could have rolled my eyes harder.

I mean, part of me would love for what she's saying to be true. I would be the first one to line up for pills, but that kinda stuff doesn't happen in real life. Oh well, it's a fun thought anyway. Maybe I could work this whole situation into a story somehow? I'll mull it over.

Marua

October 17, 2018

Dear Diary,

Nicky has been complaining about her breasts being tender and more sensitive. She's constantly massaging them now, even in front of me. She says she has to it's the only way to make them feel better. She always makes sure to take her pills in front of me. She's also said that her friend told her to only take one at a time, but she's taking two to prove she's right.

I can't believe Nicky is pushing this so far I can't wait till she runs out of those stupid pills and I don't have to hear about it anymore. Also, Nicky didn't listen to me about doing her clothes in warm water because her tops look like they've shrunk a little. Her sweaters all hang above her belly button now. I told her, but she never listens. She had better not think about borrowing my clothes.

Marua

October 19, 2018

Dear Diary,

Nicky came waltzing out in front of me in just her bra and panties today. Jutting her tits in my face she pointed to them and said "ha! See they are getting bigger!" Her tits were spilling over the tops of her bra like too much dough in a bowl. I never noticed how creamy white Nicky's skin is. I still told her to stop messing with me. It was obviously just an older bra she put on that she had outgrown years ago.

She kept insisting that it wasn't she only brought it a few months again. She seemed to get pretty upset that I didn't believe her. That's what she gets though. She's always telling little fibs and white lies. Though she took another pill and said she's going to take three from now on. I don't know, what if she is being serious?

Marua

October 20, 2018

Dear Diary,

What a day I.... I'm so confused Nicky came out of her room today topless demanding I rub her boobs. She took my hands and put them on her tits. I don't think she's lying anymore they felt huge in my hands. She told me to squeeze her boobs and I did.

I started off gently but she kept telling me to squeeze harder. So I did. Nicky moaned when I did. I started to feel really weird and went to stop, but begged me to keep going. I did and that's when I saw it. Little white drops coming out of Nicky's nipples. She's actually starting to lactate.

Once I said as much to her she let out a triumphant whoop, exclaiming she was right and put her top back on. She then took her three pills and went back into her room. I went to my room then too. I know it shouldn't, she's my sister after all, but knowing, feeling that she has gotten bigger.

Knowing that she is starting to lactate. It turned me on so much. I masturbated for like two hours just thinking about Nicky's boobs getting bigger. I know I shouldn't think about Nicky like that but I just couldn't help it. I was so horny. Just thinking about it is turning me on again. I think I need to go play with myself some more.

Marua

October 23, 2018

Dear Diary,

I think Nicky is growing faster than before. Maybe three pills are too many? She said she's gone up a few cup sizes in just days. It shows too, her tank tops are now stretched tightly across her breasts. Even her sweaters are getting filled up. Her nipples are bigger too; they poke out from her top constantly now. Plus, there's always wet spots on her tank tops now in the morning. Nicky's stopped wearing bras now she said there's no point when her boobs are just going to keep getting bigger.

Just hearing her talk like that ohhh it does all the right things to me. She knows that too, and she likes to see how squirmy I get when she starts talking about her big, creamy, milky breasts. Though I think she likes it when I play with her boobs too. She's gotten me to rub them two more times since the last time. She says she just likes to tease me, but I don't know. She gets awful red in the face when I do it.

Seeing the milk start to pour from her breasts now I swear I just want to suck on her tits. I've been spending way too much time in my room masturbating lately. I can't help it; this is just driving me wild. Speaking of which, I think it's time for another session before bed. I can't wait to see how much bigger Nicky gets tomorrow.

Marua

October 24, 2018

Dear Diary,

The milk tasted different today. I asked Nicky about it and she said she finished off the carton last night, but figured I would want some milk with my cereal. So she just filled up the carton with her own milk. She said she didn't realize it tasted funny and was going to throw it out. I stopped her and told her it was okay. In fact, I told her she should keep doing it. Milk is expensive, having our own personal supply will save money.

I went out and picked up some glass bottles for her to fill up from now on. Those cartons aren't designed to last forever. Plus, we can wash and reuse the bottles.

With that said, honest holy shit I can't believe she's pumping out enough milk to fill up a carton of milk now. It tasted so good too. God, I wonder what it would taste like coming from Nicky's nipples. Still warm and fresh. Unnghh just thinking about it makes me, I have to go finger myself. God Nicky is turning me into such a horny freak.

Marua

October 28, 2018

Dear Diary,

Holy cow Nicky's boobs are getting big. They're like volleyballs now, they're just so big and round and fat and milky! I can't take my eyes off of them when she's out of her room. I try not to let Nicky catch me looking, but I know when she does. She always lets out this playful giggle when I do.

I had to go get more bottles for her to fill. I thought ten would be enough to last us for a while, but she's filling those up by the end of the day now. I picked up another twenty hopefully that will do her for now. Half a shelf in the fridge is now dedicated to Nicky's milk.

I've started just taking bottles from the fridge to drink now instead of water. It tastes really good and the milk will go bad if we leave it. Plus, and this may just be wishful thinking, but I think drinking Nicky's milk is starting to make me grow. My bra felt a little tighter the other morning.

God, I thought I was horny before I can't imagine how horny I'll be if I started growing myself. Speaking of which I've got an hour before bed I'm going to see how many times I can cum before bedtime. Last night I got up to six maybe I'll try to get ten this evening.

Marua

October 30, 2018

Dear Diary,

It's the day before Halloween, I'm super excited I love, love, love Halloween. I remember when Nicky used to take me trick-or-treating. Then we would stay up late watching scary movies and eating my candy. It was the best. I guess we grew apart as we got older. I don't know, I know I was annoyed when she first moved in and we obviously got off to a rocky start. But now I'm really starting to like having her around.

Since she started growing her boobs bigger we've been spending more time together. I've talked a lot about how hot it makes me, but there have been more chill times too. She was teasing me the other day with her boobs. Crawling on top of me pressing her breasts against mine. Talking about how much bigger her's were.

Then after teasing me she kinda just settled on top of me and we lay on the couch cuddling together watching a movie. It was nice you know. I haven't had anyone to cuddle with, in a while. It made me realize how lonely I've been. Knowing Nicky is here with me is comforting now. Maybe I've been too hard on her all this time. Anyway, we're going out to a party tomorrow we're going to dress up. It should be a great time.

Marua

November 01, 2018

Dear Diary,

Holy shit, I think I sucked on Nicky's tits last night. I can't remember, I was so drunk last night. I remember going to the party. Nicky dressed up as a cowgirl and not like a yee haw, ride 'em high, draw, kinda cowgirl. The ears, tail, bikini, anime waifu kinda cowgirl. She kept calling her boobs udders all night which just turned me on.

Everyone was pretty awestruck by the size of Nicky's boobs. She just said that's why she wore sweaters she didn't want the attention. Nicky kept feeding me Baileys and milk. They started cold, but as the night went on the drinks became warm. I know Nicky started using her own milk instead of milk in the fridge. I didn't say anything because I thought it was kinda hot.

Then the shots came out and things got kinda hazy. I remember the two of us getting home both very drunk. Nicky insisted I sleep with her in her bed. She didn't want to sleep alone. I remember the two of us just kinda stripping off and crawling into bed. I remember cuddling into her boobs. I think I started to suck on them then. I don't know, I can't remember right.

Anyway, this morning both of us were in rough shape. Neither of us moved till well into the afternoon. We just lay in bed cuddling and sleeping off our hangovers. I don't think Nicky remembers me sucking on her boobs. If she does she hasn't said anything.

What if she just keeps making more and more milk? What if I tried to drink all that milk? I don't know if my belly could take that? How big would it get if I just drank it all...? fuck I gotta go masturbate.

Marua

November 03, 2018

Dear Diary,

This morning Nicky woke me up with her moaning. She was playing with herself again. I think her boobs getting bigger is making her more promiscuous. She plays with herself a lot now. Of course, hearing her playing with herself only made me horny so I started to play with myself too.

I spend so much time horny now it's starting to affect what I take. I used to only use a small vibrator to satisfy my needs. Today I used two vibrating dildos in my pussy and the small one I slid up my ass. God, it just feels so good to cum while thinking about Nicky's boobs getting bigger and milkier.

Plus, her tits are getting so big now they're bigger than beach balls I swear. Nothing she has fits her anymore. She still wears her sweaters, but they're only big enough to cover her boobs now. So her midriff is always showing. Nicky's got a little bit of chub on her belly that's super cute too. I know I'm not supposed to, but I'm really starting to crush hard on my sister.

Marua

November 6, 2018

Dear Diary,

Nicky's boobs just keep getting bigger and bigger. It's amazing. They're basically the size of yoga balls now. Plus, today she asked me to help milk her she couldn't reach her nipples anymore. Speaking of bigger her nipples are getting huge too. We went into the bathroom to milk Nicky's breasts. As I milked her Nicky couldn't stop squirming and she looked really red in the face.

When I asked her what was up she said that milking her breasts gives her a lot of pleasure and she was embarrassed. I told her it was okay and that she should embrace it. I wouldn't mind. After that, she was much louder as I milked her fat udders into the tub.

By the time we were done both of us were plenty red in the face and we had managed to fill half the bathtub. If this keeps up we're going to be able to bathe in the stuff. After I finished milking Nicky she quickly excused herself to her bedroom. I listened at her door long enough to hear she was masturbating in there.

That was all I could take before I had to deal with my own urges. It was my first time doing either, but I fisted my pussy and my ass today. Fuck I came so hard. I like what's happening to us. I'm going to keep drinking Nicky's milk I think that's what's causing us to be so horny all the time. I really wish I could watch Nicky masturbate with her giant tits. That would be so hot. Mmm I think I need another round of me time.

Marua

November 7, 2018

Dear Diary,

Nicky kissed me! I was helping her milk her boobs again this morning. When they were drained she pulled me between her breasts and kissed me! It wasn't like a tender I love you as a sister kiss. It was a, I want to suck your tongue kinda kiss. I was so shocked I didn't do anything.

I know I've been going on about feelings for my sister, but those were just some naughty never gonna happen kinda thoughts. She actually kissed me though! I don't know how I feel. Once she did it, she said she was sorry and then ran to her room. I'm almost more impressed by her ability to run with those jumbo juggs.

Still, she kissed me! She kissed me! She kissed me! The more I think about it, the happier I get. I should have said something. Maybe I'll go talk to her, it's kinda late, but I really should clear the air with this.

Marua

November 8, 2018

Dear Diary,

Last night was amazing! I went in to talk to Nicky and there she was just laying on the bed, naked. Her breasts were so massive they were nearly as wide as her bed. Her eyes were red and puffy; she had been crying. Seeing her there like that so vulnerable yet sexy I couldn't help myself.

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