"So nervous! Will we get caught!?" A reverse NTR encounter with my girlfriend's friend drives me to the brink of madness! Sexual intercourse where I have to hold back my moans! 4 hours ERDM-100

My girlfriend brought a friend over, so I pretended to be a good guy, but that friend was actually my type! After a while, while the three of us were hanging out, my girlfriend fell asleep, leaving me and my friend alone. A certain atmosphere developed. I didn't want to upset my girlfriend, nor did I want to cause any trouble… so I was feeling sullen and annoyed. Then the woman said, "If we really want to do it, let's do something else." Huh!? Is that okay? So, next to my sleeping girlfriend, I silently engaged in lewd acts…