I have a friend who patted my in the showers in school but nobody saw him do it.?

I go to his home together after school because my parents aren't home and i'm locked out until they do get home. He lives across the street from me. On that day he patted me, at his house he talked me into taking a shower with him. I didn't see anything wrong with that because his dad has a big shower thing in the celler and its like a school shower with 4 shower heads. We were showering and he kept talking about and asking me if I ever had it done or did it and I said no then he said he wanted to see what it was like to give sombody oral so I joking said ok. He got in front of me and he did it to me. Now I am afraid he will get me to do it to him. He is always trying to talk me into doing it. I keep saying no and I am afraid he won't let me stay in his house if I don't soon do it. I don't have anyplace else to go and it's getting too cold outside to wait for my parents to get home. If I just do it and get it over with, will he leave me alone? what if i like it?