A person who has romantic interaction with, (but not all) males and females. They are not slutty, or attention whores, or greedy. They will leave you for a man, or leave you for a woman. In the end, does it matter? sexuality
Someone who has a romantic feeling towards both genders. No, they aren't confused. No, they don't like everyone they see. If you're a total asshole, they're not going to like you.