Wife's New Trainer

"Bye honey, I'm off to Coach Rick's house again!" my wife Michelle called, grabbing her purse and her sunglasses, walking over to where I was sitting and planting a kiss on my lips.

"Again?" I asked in surprise. This was the second workout of the day.

"Yup," she affirmed. "The state competition is in two weeks and he says I need to spend as much time with him as possible before it if I'm going to win! Also I'm going to stay for dinner. He says I need to stick to his diet. Anyways, toodles!" She turned confidently, and my eyes followed her huge, firm backside as she walked out the door.

It upset me to see my wife's ass keep growing and knowing I could do nothing with it. Ever since met Coach Rick, and quit her job at the bank to pursue a career as a female powerlifter, our sex life has disappeared. She and he just clicked, and went from working out every day together so her telling me he wanted her to become a student of his full-time. I was hesitant, but accepted, wanting to help her fulfill her dreams and be supportive. I wouldn't had agreed had I known what I was in store for.

I began seeing her ass getting much bigger after a few months. It had always been big, but after going on Coach Rick's high protein diet, it became massive. Being an ass man, I loved this new development... until she informed me Coach Rick had forbidden her to have sex, due to reduced performance in competition. I pleaded with her to reconsider but she was a steadfast believer already in his program, and I soon found myself masturbating daily to pictures of her ass, and just thought about it constantly. She knew it was hard, and sent me nudes frequently to help, but it just wasn't the same.

Her competitive career took off, however, and with her program and new assets she began winning every competition she entered. I knew Michelle was strong, but with her new commitment she began dominating the competition. She would go on week-long trips with Coach Rick to competitions. I was jealous of him spending so much time with her, but I trusted that they kept it professional.

The reason for my trust was that she was extremely open and would tell me everything that happened with him. When she told me about his gluteal massages in between squatting workouts, I boiled over in envy. I barely even got to touch her backside, and he got to out his hands all over it? I couldn't let her see my jealousy, and so I pretended it was fine. I did have something to say when she told me that he had allowed her to masturbate now, but required that she do it in his presence.

"It's backed by science, darling," she said reassuringly. "He stays in the room with me while I make love to myself to strengthen the student-coach bond. The studies show that with a stronger bond comes stronger performances."

When I asked for these studies, she insisted that Coach Rick told her they were circulating the high-level workout community and were not available to the public yet. I was furious at the thought of another man being in the room with my wife while she pleasured herself. I knew how horny she would get after having orgasmed, which really bothered me knowing he would be around her in that state. I trusted her completely, but after having cum I knew she wasn't in the same mindset.

"Honey, there's nothing to worry about!" she argued one night after we had been having a fight about this. "Rick is a sweet guy! He cares so much about me! He preps my meals, he picks me up to go workout! You have nothing to worry about!"

"But he gets to watch you masturbate!" I cried. "I don't even get to pleasure you anymore! He's more involved in your sex life than I am! I don't care if he doesn't physically touch you, it still bothers me!"

Michelle bit her lip and dropped her eyes.

"What??" I asked, my heart sinking.

"Well... promise me you won't get mad... but he did touch me once. But honey it wasn't his fault! I had just orgasmed using my vibrator and it was simply amazing. I was on cloud nine, and you know how I am when I cum... or, knew how I am... anyways, I... I had this feeling when I came that my anus just felt empty! So... I asked him to stick a finger in there..." she admitted, flipping her hair back as a smile crept onto her face.

"You... you did what?..." my voice squeaked in disbelief.

"Oh darling, don't be mad, it was just one time!" she said soothingly, wrapping her arms around my neck. "I just got caught up in the feeling."

I sat there in shock, feeling the most intense jealousy rise up inside me, thinking of another man with his finger inside my wife's big, beautiful ass.

"How— how was it?" I asked against my better judgment.

"Ohhh, honey," she moaned in a deep, lustful tone, her eyes rolling back in her head as she closed them slowly. "I've never cum so hard... I was just in heaven for those 45 minutes."

"45... 45 minutes?" I gasped, my heart dropping through the floor. I wished I had never asked, but yet part of me wanted her to keep talking about it. Part of me wanted to know every detail.

"Yes," she admitted, her eyes wandering up to look into the distance in fond recollection. "I lost count of how many times I orgasmed with his finger in there. Might have been 30, might have been 100. It just felt like one endless orgasm. I never knew a finger could do so much... and I never knew I could feel such intense pleasure out of my big old ass!" She bit her lip, then turned and looked at me.

"Oh, honey, you look white as a ghost! Don't be jealous darling, it's a bad look on you! Coach Rick has the utmost professionalism, it wasn't like we were cheating! Plus I'm being open with you! It was for our student-coach bond, that's it! Nothing more!"

"Alright," I mumbled, accepting her kiss on the cheek. I was fuming inside, but I couldn't let her see it. Maybe it was all in my head, like she said.

"I'm glad we're on the same page," she said cheerfully, jumping to her feet. "Now I'll be off to Coach Rick's for dinner and then I'll be staying overnight for a workout in the night and then the morning! But don't worry, I'll send you some pictures of my bottom, so you don't get too lonely!" she chuckled, blowing me a kiss as I watched her huge, protruding rump bouncing out the door without a second glance.