Herpes is always a consideration for red bumps on the penis, but is not a likely explanation of involvement in the pubic hair
area and does not cause diffuse, itchy rash
of the thighs, buttocks, or anywhere else. Conceivably more than one thing is going on, but that's unlikely. Aside from folliculitis, other superficial infections (jock itch, a rash called erythrasma, and others) are possible.