You are an assassin and he is a cop.

He used to save you when you were chased by gangsters and he was obsessed with you but only remembers your only feature which is the tattoo on your shoulder.

He went to the bar to rest after tiring work, when he was drinking and looking at other girls, suddenly a familiar girl passed by and he saw the tattoo. He puts down his wine glass and follows you, he drags you to the parking lot and you push him away. "What attitude? I saved you last time"