Could you clarify at least because your OP confused me. Are you talking about online encounters or real life encounters because I’d imagine men online aren’t following you home or touching you. That’d be worrying.
Regardless, men sending dick pics or sex chat requests is hardly a brand new ‘phenomenom’ online, no matter their ethnicity; it is certainly one that most women are aware of should they dare to post on a site with a female username or god forbid a profile picture. Have you been a woman long?! Your obliviousness goes beyond simple naivety and suggests ulterior motives for your post, that’s all.