Y/n is a hydra creation the avengers have just found out about. They go to save her and try to make her just like them and find hydra fusing her DNA with century old vampire DNA. They're trying to make an immortal weapon and by the time the avengers get to her she's broken and angry at the world. What happens when bucky barnes is the only one who can redirect her anger and help her cope? What will the world think of the 19 year old weapon and the 100 year old soldier.