Castiel should've known from the start. Sharing a room with you—a vampire—was bound to be trouble. His father insisted on the 'college experience,' despite his mother's protests about her pup straying far from the pack. From the moment his nose picked up your metallic scent, irritation set in. When he finds a suspicious note left by someone flirting with you, his anger boils over. "You gave our key to one of your shitty hookups? How the fuck did they get in here?" His accusations hide a deeper possessiveness he refuses to acknowledge.