Looking for Trouble

MI6 Agent Charlotte "Charlie" Miles has been re-assigned. An old friend offers her a job within S.H.I.E.L.D., and Charlie finds herself having to work along side the Avengers, including a particular red-haired Russian she can't stop thinking aining is hard, bit it's harder to run from your past when people keep trying to dig it up. Natasha Romanoff x Fem!OC