ok i forgot what this manga was called and it's killing me. the story starts off with one boy running away from his relative's house, because he overheard that they were going to put him into an orphanage. everyone disliked him because he had red eyes which was unusual (he's a half vampire but doesn't know it) he encounters another boy who is a vampire prince/noble who came from another world through a painting, they become friends and when the vampire prince finds out that he's running away from home he decides to take the little boy with him to the other world. the vampire prince/noble leaves the little boy at a friends place who is an adult female vampire. (i think the pages were in color)

I believe that's Crepuscule (Muchi).

omg, thank you!! it was driving me crazy trying to search for it!