blood bank?
Are you referring to this manhwa? Especially at ch36
https://www.mangago.me/read-manga/murderer_llewellyn_s_enchanting_dinner_invitation/
I don't think so
No
https://www.mangago.me/read-manga/love_sick_dog/
is it this one?
No, but it looks interesting
I forgot if it's a manhwa or a manhua but it's about a black haired dude (I guess?) Found a blond dude chained from his neck and wear something like dogs wear on their mouth so that they don't bite human. I forgot the rest
All I know is that story is bl