Boyfriend should wear deodorant?

It could be that he does use deodorant but maybe the one he uses is not good enough. However, what is wrong with telling him that he has body odor and that you mind it? What you can do is next time you get together, you can just say, 'hey, have you been out playing with the boys? I think you need to take a shower.' :D Honestly, you're doing him a favor by being straightforward with him. Or if you want to be a bit more diplomatic, next time you're together and he smells, you should tell him, 'hey, I think I need to shower cause I stink.' And if he says you don't, then you say, well, what is that smell then? :P