Bucky is an Avenger, Steve and Sam's best friend. He's got a metal arm and he has a deep secret.. he's in love with the villain.. Y/N Stark, Tony's twin old brother..

Y/N was at hydra his whole life, like bucky ways. Y/N is a super soldier and speedster. But bucky loves Y/N, thinking he don't love him back.

Bucky was watching Y/N, since the Avengers got Y/N finally. Bucky asks why happened and made him turn villain. Not knowing Tony, Y/N's own twin, hurt him enough.