look , im 21 , i have the same problem if i try to shave with a razor , its simply razer burn , you shave , the hair is thick and pores get inflamed , then are blocked due to inflammation , just like razor burn on your face it causes "pimples" per say , they can get big like pimples too , therefore i now shave with a beard trimmer that doesnt shave down to the skin all the way , i dont care if its ruff or not =P just be careful with his balls lol nothing like a pair of clippers biting your sack it hurts !! lmao im serious tho , just razor burn , simple. you said he shaved and got bumps .. thats common sense