Quill is a sad-eyed little man.
A Feast for Crows
When Arya Stark is disguised as Cat of the Canals, she encounters the mummers of the Ship, including Quill. The playwright offers to teach her how to kiss like a woman, but Tagganaro puts an end to that when he hits him with a codfish.
The Winds of Winter
This information has thus far been released in a sample chapter for The Winds of Winter, and might therefore not be in finalized form. Keep in mind that the content as described below is still subject to change.
Prior to the first performance of The Bloody Hand at the Gate, Mercy spies Quill standing in the back of the playhall. She thinks he has come to see what he can steal from the performance for one of his own plays.