What Causes Redness On The Rim Of The Penis?

I noticed a small reddish section on the rim of my penis foreskin. from left side to right side. its now about from 6 months. & first time i saw it & feel it during masturbation. skin appeared to be shinier than the rest. no rash, itch, pain nothing. Although the discoloration has become less noticeable, it is still there, I also notice that it becomes more red after masturbation, and slowly returns to normal if I leave it alone for a while. For masturbation, the area is where I tend to rub the most. there generally isn t any pain, though it does hurt a little bit if I engage in repeated activities. im 100% sure its not a std or hpv. look like friction burn. is it?