Faiselle is stocky and square faced. She owns silks with dense green embroidery. 
Being a Sitter in the Hall for a time means that Faiselle is also a high-ranking sister and a strong channeler by Aes Sedai standards. Thus she has the strength needed to use the travel weave. Faiselle's strength is given in the "Wheel of Time Companion" as 20(8).
Faiselle is Domani and is 171 years old. She was born in the year 829 NE and went to the White Tower in 845 NE. After spending ten years as novice and ten as Accepted she was raised to the shawl in the year 865 NE.
Her Ajah Head, Adelorna Bastine, sent her to the rebels because she was not invited to the vote to depose Siuan Sanche and raise Elaida a'Roihan. This would help keep her safe, and allow the Ajahs to help defuse the rebellion. She has allied herself with the Salidar Aes Sedai and is a Sitter in the Salidar Hall. She supported Lelaine Akashi because it would help stalemate Romanda Cassin and make the rebellion easier to control.
She votes NO on the Rebel Aes Sedai declaring war on Elaida.
She is one of the Sitters that want to begin negotiations with Elaida's White Tower. She votes NO in the Rebel Hall of the Tower for an alliance with the Black Tower. She is part of the group that negotiate with the White Tower Aes Sedai in Darein.
She believed that the Seanchan were a threat.
She bullies Myrelle Berengari into bonding Llyw, after Kairen Stang's death. Lelaine calls an emergency meeting of the Hall. Jahar Narishma arrives with the offer from the Dragon Reborn of bonding forty-seven Asha'man. Faiselle opposes this motion and refuses to stand with the greater consensus when the offer is accepted.
Faiselle remains a Sitter when the Hall of the Tower is re-united after the White Tower Schism. The Sitters try to hold a secret meeting without Egwene, discussing ways temper the Amyrlin's power when a declaration of war is called. Faiselle voted for a proposal that would allow only Egwene to deal with the monarchy of the world, which includes Rand as he is King of Illian, while the Hall would take over prosecution of the war and deal with Gareth Bryne's army. In that same meeting, Faiselle voted in favor of the new rules and procedures in the Hall, which included temporarily replacing a Sitter when she is absent from the Hall and that no meeting of the Hall can commence without all Sitters and the Amyrlin Seat being present.
During the Last Battle, she accompanies the Aes Sedai army. She is present when Gareth Bryne's Compulsion is revealed, and suggests that the Sitters take command of the army. However, Egwene recommends leaving the command to Mat. She presumably survives the conflict.