Y/N doesn't belong to this world and yet knows everything about it. No she isn't an alien researcher, she just have all the answers. The only thing she doesn't know is about herself. She doesn't know what is the source of her powers. She doesn't know anything about her parents or the planet she belonged. She doesn't know since how many years she is living on earth. She doesn't even know her actual age! She's been living on her own for all her life. That is when she met Bucky.