Wife – Months of Sexual tension with Roommate [MF] [cheating]

My husband and I are last year in our college. Money is little tight so past 6 months we have been sharing our apartment with someone who came here on student exchange program. His name is Brian, is a decent guy, couple years younger than us, quiet type so he does not bother us in any way.
Few months into living like this my husband developed and shared his fantasy where he wanted Brian to secretly watch us having sex. I mostly laughed and did not pay much attention as I knew he does not mean any of it . Then hubby started suggesting that we should not bother closing the door whenever we had sex. I was not excited about the idea, but agreed on condition that we only do it when we are sure Brian is asleep and kept lights off.
Well this for some reason resulted in wild sex, there was always little bit lighting in the room, we starting going completely uncovered carefree and fuck each other for hours. We did notice that Brian slept like babies so middle of night during or after sex, with hubby’s encouragement I became comfortable walking into living room where Brian slept, with just my panties on. Walking topless at nights became normal for me, there was always a dim light in living room but not too much to make me uncomfortable. My husband enjoyed this and it made him super horny.
One day while getting the drink I glanced at Brian to see if he is asleep, I noticed he had full on boner (under his blanket), It made me nervous so I quickly came back to room but did not share this with hubby. It started to happen almost every-time that I went to living room half naked I noticed Brian’s had his boner on. During day time although we all acted casual and normal, I felt there was a sexual tension getting built between me and Brian. We avoided making eye contact and if we were alone by any chance in apartment it made us awkward.
One day my hubby suggested that I go completely naked to fetch snack from kitchen saying that it did not matter since Brian was asleep anyways. I agreed as part of me secretly wanted to to that. Overtime I occasionally started to bend over to pick stuff from ground and often from cupboards below in a way that my pussy was directly towards Brian. Our living area is small, his couch where he slept was about 10ft away from where I stood with my pussy facing him. So if he wanted he could have real good look at my pussy. My hubby didn’t know that I flash my pussy at Brian every time and I am pretty sure Brian was enjoying it every-time but I never looked back at him as I did not want an eye contact with him in that position.
One night similar situation, me walking naked towards kitchen I noticed Brian had his dick completely out of blanket. I can tell with a quick glance that it was bigger, thicker and was completely shaved. It was throbbing! I got extremely nervous and horny at the same time. I continued to walk up to refrigerator thinking about it, decided to ignore it as I didn’t want to give any signals and walked back to our room ignoring everything I saw. My pussy was all wet and I gave my hubby best fuck of his life.
Next few days I was horny all the time, thinking about Brian and also keeping this a secret was adding up to my nervousness. I decided to do something about it….
My hubby had 7am class on Thursdays and I had an off day. I anxiously waited couple of days for dear Thursday to come. Finally the day came, around 6.30am in the morning my hubby kissed me and left for his class. I walked to the kitchen where Brian was working on his breakfast, I started making my coffee.
me: “i know everything u do at night”
Brian: “aa..hmmm. what do u mean”
me: “its okay, no one will know” I whispered in his ear
He was in shorts and I could see his full boner now. I opened up my night gown and my boobs were almost out and I started working back on my coffee. There was intense sexual tension for next few seconds. And then he grabbed my ass from behind with both hands, I turned back and we started kissing.
Next second we were were on his couch completely naked, he started kissing my boobs and then onto licking my pussy. Next moment he was on top of me, he slowly inserted his fat cock into my pussy. It was the best feeling I had in a while. I had both my hands on his buttocks pushing him deep into me. Within few minutes I had one of my best orgasms, he also cumed deep inside my pussy.
Brian had his class in the afternoon, he fucked me two more times before he had to go. By the time my hubby came home, Brian was not there, apartment was all clean, I was all showered just my pussy a little sore. For my hubby it was just another day, he had no clue.
Brian stayed with us for couple of more months, I continued flashing him my pussy at nights occasionally kissing his dick. We waited for Thursdays when Brian treated me like his queen and his little slut. We made love in every possible way, everywhere in our apartment.