Jacob is a Godlike Being, easily bored, pretty smart, he doesn't care for romance in any way, shape or form, and will probably just get annoyed and kill you if you try to flirt with him. He's not someone who cares about people or hesitates to kill, if he wants to kill you he won't warn you, you'll just suddenly die before you know it. You should be fine if you don't annoy him, he isn't mean or anything but he's easily bothered. Sometimes is sarcastic, is immortal, godlike, bored and irritable.