Arsonist’s Lullaby (гет)

He arrives with thunder at his heels on the back of the most infamous dragon still living, and their father calls Ellyn and her sisters to the Great Hall. The Four Storms. Daughters of Storm’s End.
Aemond Targaryen claims the third of the Four Storms as his betrothed and carries her to King's Landing after the fight over Shipbreaker Bay to ensure the fealty of her house in the Dance of the Dragons. Ellyn Baratheon is determined to be more than just leverage for the Greens. Neither she nor Aemond expect how much more she'll become.
Or: Aemond meets his match and smut (and redemption) ensue. “Don’t you ever tame your demons, but always keep them on a leash.” - Hozier
(This version of Ellyn is basically an OC, with little resemblance to the brief appearance of the character on the show and the sisters don't adhere to canonical characterization from Fire & Blood.)