I’m thinking that her coat gradually darkens and gains black markings as she ages and fully acclimatizes into her role as the Stars, gaining a closer resemblance to her birth mother, Belladonna.
@Storyhunter
This one here doesn’t ‘directly’ have anything to do with Portal, but is part of a crossover AU (KirinDOS) which heavily involves the games (particularly the cores).
Edited
This one here doesn’t ‘directly’ have anything to do with Portal, but is part of a crossover AU (KirinDOS) which heavily involves the games (particularly the cores).