What causes pimples, or boils in groin?

Often bacteria. The groin is a common place to get boils or "pimple like" lesions. Naturally occuring bacteria like staph is on our skin, and sometimes shaving, or small infected hair follicles can get inflamed and irritated causing boils, absceses, or pimple like lesions. You should see a dr. And get an exam and proper treatment, good luck.