S1·E22 Don't Be.

Asuka's synch rate is on a downward spiral after her defeat at the hands of the Fourteenth Angel, Zeruel, and her frustration with Rei, Shinji, Misato and Ryouji is on the rise. Angrier and more disturbed than ever, she is forced to relive her dark, traumatic past during the encounter with the Fifteenth Angel, Arael.