White Lily is a white horse with a bad temper. Zero often skips classes and sleeps in the horse stables, near White Lily. She appears to be protecting him while he sleeps. In the anime, she even tries to hide Zero's blood tabletsfrom Yuki's prying eyes. White Lily also appears to disapprove when Zero yelled at a girl who tried to give him chocolates.
White Lily first appears in the manga Chapter 1 episode 6. None of the students wanted to ride White Lily since she has such a bad temper. White Lily is suddenly spooked. She kicks Yuki and bolts. Zero is sleeping nearby under a tree. He warns White Lily to not disturb him. She rears to trample him. Zero acts quickly, jumps on her back, and brings her under control. The Day Class students are amazed at Zero's skill. Zero guesses correctly White Lily was spooked by a bad smell. The window of the Moon Dormitory had been opened, and the scent of vampires scared her.
In the manga special edition, more background information is revealed about White Lily. Zero does not understand why White Lily is not afraid of him. He is a vampire, and surely she can tell. The stable caretaker makes fun of Zero, and calls White Lilly his "girlfriend." Zero dismisses this and says she only likes him because he fed her milk when she was younger.
White Lily is a metaphor for Zero. White Lily shares traits with Zero: they have similar coloring, they are both hot tempered, and they both are protective of loved ones.
The White Horse (The Knight)Edit
Zero's symbol in Kaname's Chessboard is the White Knight (Horse). Throughout the first act of the story, Kaname's plans for Zero are revealed by where he places the White Knight. Sometimes he abuses the White Knight by thumping it in the head after Zero drinks Yuki's blood, and then later scattering it into pieces once Zero's sire, Shizuka Hio, is destroyed. In the anime open, Yuki runs on a chessboard full of giant glass chess pieces. When she drinks the vial of blood, Zero suddenly appears in the Knight chess piece and shoots his gun at her. Firing his weapon breaks the Knight chess piece. At the climax of the first act, Kaname calls Zero, "The Horse" (Knight) he has carefully raised, and commands him to kill Rido. Zero is Lancelot (the Knight) in the love traingle.