I noticed this about a week ago.. When I retract my foreskin and I look at where my frenulum connects to the glans, there is a sort of build up of a whitish skin/flesh. It is only along the frenulum then it stops. At first I thought it was that buildup you sometimes get if you don't wash well, but it didn't come off. It doesn't hurt or anything.

I'm 19, haven't had sex, so not an STD. What is it?