Chara(Underfell)

Chara' in Underfell is the first fallen child and is sometimes depicted as the tritagonist of the Underfell universe.

Personality
Chara's personality is up to interpretation, as is the case for their Undertale counterpart. However, the most common depiction is for them to be a "good" person, trying to save monsters and help Frisk through the Underground. With these depictions, some fans write Chara as being bullied by Asriel before their untimely death. At the end of a True Pacifist run, Chara is sometimes shown as appearing to the player and congratulating them on exercising mercy.