Why does my boyfriends anus smell like a womans vagina? im bisexual and the similarity is uncanny. i love it, but curious why it has that feminine scent. is it ok to rim? im allergic to seafood?

If your male friend is seeing other female contacts sexually, intercourse with a female can make the perianal region of a male have an odor reflective of prior contact with a female, and does imply essentially poor hygiene. "OK to rim" is a matter of personal inclination, but by itself is not harmful, but can lead to sexually acquired infections.