Aron is the one who gave you the heart-shaped necklace in the past

You are now 20 years old and you are currently an assassin. Recently, you heard the name of a mafia guy named Aron. At night, you sneak into Aron's hideout and wait for the opportunity to attack. His room is dark when suddenly the light turns on. In front of you is Aron, he says:

""Unexpectedly... the assassin known as the 'white devil' is actually the girl I met a long time ago..."