Redness and irritation of male genitals

Patient: I am a 20 year old male with a somewhat extensive sex history, i am currently in a relationship and in the past few months i have noticed redness and irritation in my genitals. There are no spots or cuts but i cant figure out what it is. After a few days with no sexual activity a thin layer of skin forms over the redness area similar to a scab but white in color. Any ideas as to what this might be?

Doctor: