К себе means "to themselves" and персонаж means a character/person/personage. All is applicable to our phrase naturally.

хотя и не привлекающий к себе персонаж - a person not attracting (attention) to themselves. We have a set phrase "привлекать/привлечь внимание", which means pretty much the same as "attract attention". This is where the whole structure comes from.

Anyway, could you provide the whole sentence, coz you know context is everything and I kind of automatically assumed a certain context here. Although, I'm sure my previous assumption was correct, but still the whole sentence will not hurt.