Making the right decision

I want to have sex with a straight friend. I'm currently in the closet myself. For context he is comfortable with me enough that he has gotten undressed in front of me a lot when getting ready to go out. I don't know if this was an invitation to look or something innocent. We've also "kissed" but more of friendly way while out with people in the bar drinking.We had recently drank together in his room. His leg rubbed off mine and for some reason I got super hard. He was wearing shorts and we were both lying on his bed. Initially there was room between us but I slowly moved closer and just kinda had my foot on his leg. He didn't move. Later he left the room to get the pizza we ordered and I took this chance to smoke out the window but bending over to show my ass (I was wearing tight tracksuit pants). I felt him looking but he did nothing. I eventually let my hormones calm down and left.Haven't been alone with him since but he's asked me to come over a couple times. What should I do?