Callas

Callas (カラス, Karasu) is a character who appears in the Kamen Rider Battride War and also the main antagonist in the game.

Biography
Callas was Foundation X's scientist that named Susumu Karashima (辛島 進). However, he was trapped in a dimension of bird cage named Mnemosyne (ムネモシュネ, Munemoshune) with his former wife, Rie Kanai (叶井 梨絵). As he became a dark evil spirit entity called Callas, she instead becomes a light pure entity named Canaria with growing wings and tails.