I have red raised itchy bumps on my butt. what could it be?

Maybe folliculitis: It sounds like you have folliculitis an infection and inflammation in the hair follicles. See your dermatologist for treatment but in the interim you can try a benzoyl peroxide wash.

Not certain: This can't be diagnosed with the information that is available. A history, physical examination & other studies may be needed to determine cause/causes. Once accurately assessed a treatment plan can be developed.