Soulmates, Soulmarks, and Loki?
(Y/N) Barton is a former SHIELD agent with the power to heal herself. In her world, everybody has a soulmate. When she first meets Loki, she discovers they are soulmates. After that, life is good, all the Avengers live together in harmony. Until she is captured by Hydra and made into the Assassin. After a year and a half, she is rescued, but nothing will ever be the same.