Tokyo Babylon Seishirou is a kind veterinarian. He joins in with Hokuto in teasing Subaru about them getting married, but always laughs it off as Subaru blushes furiously.

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Tsubasa: Reservoir Chronicle A vampire hunter who chases after the vampire twins (Subaru and Kamui) across worlds. By exchanging his right eye, he received the power to cross dimensions from Yuuko Ichihara, the Witch of Dimensions. He was also the one who taught Syaoran how to fight.