Sapphire
                        
Sapphire is the brother of Prince Diamond.Sapphire is the keeper of the chamber where the Negamoon's Dark Crystal rests. He is the quietest, most reserved, but also probably the smartest of the family. He is probably the first to realize the perhaps the Wise Man is using them. He's also very jealous of Neo-Queen Serenity for having stolen Diamond's heart. He tries to warn Diamond about the potential danger of trusting the Wise Man, but Diamond refuses to listen.Sapphire, however, is committed to defending and protecting his older brother, so when he confirms his suspicions of the Wise Man's intentions, Sapphire steals the key to the Dark Crystal, but the Wise Man attacks, seriously wounding him and forcing him into hiding, giving the Wise Man time to convince Prince Diamond that Sapphrie is a traitor. The four sisters soon find the wounded Sapphire and take him in, and it's there that the relationship between him and Prisma is revealed. However, Sapphire cannot stay (despite Prisma's pleadings). He still has the Wise Man to deal with.

Sapphire approaches the Dark Crystal and finds himself up aginst the Wicked Lady. However, the Sailor Scouts (having been informed by Catsy) intercede on his behalf, giving Sapphire time to explain to his brother that the Wise Man has betrayed them. Suddenly, though, the Wise Man attacks suddenly and without mercy, ultimately hitting him with a fatal blast. Sapphire's death, however, would not be in vain. In those final moments, he still managed to protect his brother. Diamond now knows the truth.
Sapphire dies in english episode 79:Brotherly Love.