So basically I'm friends with this guy... kinda like a friends with benefits type thing and sometimes we flirt with each other, say dirty things, and the other day I came up and sat on his lap. I moved around a lot to get comfortable then suddenly he just went still and quiet and bit his lip, I think I heard a deep groan somewhere too? Did he like it or? Another time I was trying to get my phone back from him and accidently pressed down on his crotch and he did the same reaction? Did he like it? Should I do it more often?