When a guy jacks off or (masturbates) too much he tends to develop a rash on the penis that can be very painfull.

a better way to describe it would be a mastur rash

The rash you get on the tip of your penis from over fapping without lubricant. The skin becomes ultra sensitive in a bad way.

That special kind of rash that develops when you've bumped uglies with some scallywag of sexual ill-repute.

a sore on the penis usually caused by friction.

Occurs when having sex for an extended period of time, vigorously, or with a woman with pubic stubble. Friction from the rubbing of the skin between the penis and labia majora will cause a rash to be produced. Symptoms include redness, swelling, pain, and sensitivity usually on one or both lateral sides of the penis in a line extending from the base to the tip. More severe rashes will usually develop a slight darkened scabbing within 12 - 24 hours from intercourse and heal within 3 - 7 days without treatment. To reduce symptoms it is recommended for the men to refrain from sex and masturbation, wear loose-fitting cotton underwear, take ibuprofin as needed for pain, and use a condom with future encounters. For the woman to help prevent future occurrences with men, shave cleanly before and use lubricant during intercourse.

An inflamation(redness) of your penis/vagina,due to a marathon(unusually long) lovemaking session

a rash found upon the penis, also an insult.