Ada Clover

Ada Clover is the older sister of Carl Clover and the daughter of Relius Clover.

Information
Ada is Carl's older sister. Carl refers to Nirvana (his Nox Nyctores) as Ada, which may suggest that Nirvana might actually be Ada, or it could be the affects of the Nox Nyctores (which cause insanity) and Carl just sees Nirvana as Ada. Carl want's revenge on Relius for something that happened to Ada.

Trivia

 * A common fan-theory is that Relius somehow turned Ada into Nirvana. Concept sketches of Carl and Nirvana back up this theory, showing Nirvana with a (naked) human torso, however seemingly robotic arms.