Dain Aetos

Violet's childhood friend, whose signet reads other people's memories.

Dain Aetos is Violet Sorrengail's childhood best friend and the son of Colonel Aetos. In Fourth Wing he is a second-year rider and the leader of Violet's squad in Fourth Wing. He is bonded to Cath, a Red Swordtail, and his signet, retrocognition, lets him read a person's memories by touching them.

Quick Facts

Dragon: Cath (Red Swordtail)
Signet: Retrocognition
Father: Colonel Aetos (a general by Onyx Storm)

Facts from the source article.

In Fourth Wing

Dain is the squad leader of Violet's squad when she arrives at Basgiath, and later he kisses her, only to find she no longer has feelings for him. Without her knowledge he uses his signet on Violet and reads her memories, and he passes what he found to his father, Colonel Aetos. The colonel uses it to send Xaden's group of marked ones to the outpost at Athebyne during the War Games, into a trap: venin attack a nearby village, and Liam is killed in the fighting.

In Iron Flame

Violet ends their friendship, blaming him for Liam's death because he read her memories without her consent. Now wingleader of Fourth Wing, Dain refuses Burton Varrish's first order to read Violet's memories. When Varrish later forces him to, Violet makes him see her memories of the venin attack at Athebyne; realising he has been lied to, he turns on Varrish and stabs him. He later tells Violet he never knew about the venin or meant to harm her, and helps her translate the journals, and the two grow closer again.

In Onyx Storm

Dain is one of the riders Violet handpicks for her squad's journey to Deverelli. On the island of Dunne he, Violet and Xaden fight champions to win an audience with the queen. When Mira's throat is cut, Sloane Mairi siphons magic from Dain into Brennan so that Brennan can heal her.