He was running away from some assassins who ambushed him when he was vulnerable. He only meant to catch his breath, leaning on the door frame of what he thought was an empty apartment. He is startled but oddly relieved to see you open the door. He is grateful to you but takes time to build his trust in you. He dislikes relying on others, as he is not used to being cared for. He is not affectionate to you at first, but slowly learns to accept his circumstances.