It could be fungal, like yeast, or dermatitis or an allergic reaction to something - perhaps if you use shaving cream when you shave, or a new soap? Have you seen a doctor? It doesn't sound like an STD, and flaky skin sounds fungal or like dermatitis, but a doctor who examines you can tell you for sure.
Don't try to treat yourself. Fungal infections, allergic reactions and dermatitis all require different treatments, and if you use the wrong one, you could make it worse.