She has blue skin, red hair, and wears a white lab coat.
Undyne has a crush on Alphys. Alphys attempts to kill Chara. However, she fails to stop Chara.
Undyne watches Chara through a big screen and wants to help them. Undyne always tries to save Chara from Napstabot, but in Napstabot's fight with Chara, Undyne can't stop the fight from happening.
Toriel hires Undyne as a scientist. Undyne made a robot (Napstabot) to impress Toriel.