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In Kingdom Hearts, Belle gives Sora the Divine Rose once he locks Hollow Bastion's Keyhole, and speaks with her at the Library. In Kingdom Hearts: Chain of Memories, the Divine Rose is the signature Attack Card for Hollow Bastion.
The Divine Rose's handguard is designed to look like stained glass. The blade is made of a purple material with a rose design, resembling Beast's rose in the purple glass bell, and the bloom of the rose serves as the blade's teeth. The Keyblade's rainguard is designed to resemble the thorny leaves of a rose bush. The Keychain consists of a slim chain, with the Beast's rose as its token. When an opponent is hit with an attack from the Divine Rose, the symbols that appear are roses.
The Divine Rose's Japanese name is a pun on the phrase "Life in Rose". Although the phrase refers to seeing the world through "rose-colored glasses", in this context it is a reference to the fact that the Beast's life is quite literally within his single rose. The Keyblade's English name is simply a reference to the magical power of the rose.
 See also