The Bird and the Imp (A Tyrion Lannister fanfic)

Lady Erin Ashwood is sent to King's Landing with her older brother, who is to become a knight in King Robert Baratheon's kingsguard. There, she is betrothed to Lancel Lannister, the Queen's cousin. She becomes friends with Arya and Sansa Stark, who is betrothed to Prince Joffrey

But outside the city walls, discord rises and after Robert is fatally injured in a hunt, Ned Stark and her brother raise doubts about the lineage of the Crown and both are named traitors.

Now branded a traitors sister, Erin must survive in the lions den as a hostage of the Crown along with Sansa. Tormented by Joffrey and made to serve as a handmaid to Cersei, she remains strong and holds onto the hope that she will escape.

But when Tyrion Lannister arrives back from the North, she finds herself falling for him despite his name and discovers that love is a far more dangerous game to play.....