it all started when i moved into my new apartment. it was building that had 3 apartments in it total. the other two apartments were rented by an older couple and a younger couple. I was a single guy living on my own. after a few days i got to know the other couples. the older couple invited me for dinner and introduced themselves very nice couple. The other couple were the same age as me. a smoking hot couple. the girl was about 5'5 130 lbs blonde hair blue eyes and the guy was about 6'1 200 lbs muscular. I knew by this time in my life i was most likely bisexual. we hung out on a regular basis seeing how we all worked the same shift. we had drinks and parties and the usual stuff a younger person would do. I instantly thought that Rachel the younger girl was sexy as hell. i hit on her from the start and her boyfriend never noticed. after a while he started to catch on and wasn't that mad about it. the more and more we hung out the more comfortable we got with each other. it got to the point that Rachel even got changed in front of me right down to her under ware and bra. and let me tell you it was a great sight. she was tan and had nice round C-Cup boobs. One day it was just me and her hanging out cause her boyfriend had to work overtime. we started talking about how she would love to add more flavor into her relationship with her boyfriend but he wasn't sure about it and she didn't ever think she would find another person to join them. I asked if she wanted a guy or girl to join them and with out hesitation she said guy. she didn't want to share her guy with another woman. i instantly started getting hard. i came out and said well i would join in a second if he was ok with it. she said she would work him into it. the next week she brought it up to him and he was still skeptical. i have always had thoughts of being with a guy and girl at the same time. Eventually she got him to agree to join but the other guy could not touch him. i know that would change when we were having fun. we all started having fun by slowly getting undressed. we were all sitting there naked and he started to kiss her and play with her hard nipples. i went right for her pussy and started licking her and fingering her until she started moaning. We were fooling around for a while and she started stroking his cock which let me tell you was nice and thick and long. after about 10 minutes of her stroking him she secretly grabbed my hand and replaced it with hers and i began stroking his cock and he didnt know it was my hand. about 10 minutes later he blew all over my hand. he was moaning and everything. He looked at her and said it felt awesome. she told him to thank me cause it was me who finished him off. he seemed shocked and looked down and saw me still stroking him. i thought when he looked he would stop me right then. he didn't and he just started to get hard again. i didn't wait another second i leaned in and started sucking his bulging cock. He moaned very loud and reached down and felt my cock as he was getting his sucked. i did not expect him to come again so soon. however i was wrong all of a sudden he pulled my head tight against his cock so he went so deep in my throat. he then slid out a little and loaded my mouth with his huge load. i swallowed every last drop. he then returned the favor and took me in his mouth until i came in his mouth too. it was a very fun unexpected night!