Fool Me Once

Aven works alone.
She doesn't want anyone's help, and nobody wants to help her. She's an assassin, and has been longer than you could believe. She's killed more targets than she's made friends, by a lot.
But it only takes one failure to topple her whole career, and send her into hiding from her employer. On the run, she soon receives help from a human named Gavin, who has no idea she's a Fae. Unfortunately for her, Fae are considered animalistic monsters by humans, and now her life potentially rests solely on keeping her secret, despite all of her differences such as faster healing and unearthly strength.
How long will it last?