Generally, if you've played your cards right, it doesn't feel like sandpaper.
I don't think it wouldn't be that hard to imagine...Wait...OP is a guy, right?
Girls generally know how it feels to get laid...just because, if they want it, they can get it.
Guys have to bend over backwards to get girls to bend over backwards, as HIMYM would put it it.
For guys, just imagine skin on skin contact, which is always nice, with the manhood in a tight, moist space.
Why does this need to be established?