Yumichika Ayasegawa is the 5th Seat officer in the 11th Division of the Gotei 13, under Captain Kenpachi Zaraki. Yumichika wears the standard Shinigami shihakushō uniform with some customizations. An orange piece of clothing sits on top of his uniform around the neck, which covers most of his chest that would otherwise be exposed by his uniform. This is connected to an orange sleeve on his right arm under the much looser fitting sleeve of the uniform. Yumichika has colorful feathers on his right eyelashes and eyebrow. He has shiny skin, purple eyes, and jaw-length black hair, which, in conjunction with the feathers, gives him a somewhat feminine appearance. Yumichika is a narcissist who judges almost everyone and everything by beauty. He is also incredibly vain. Yumichika is a powerful combatant and wanted to become the third Seat of his Division, as he thought the kanji for the number three was the most beautiful. However, Ikkaku Madarame took it, so Yumichika took the fifth Seat, as he thought that the kanji for five resembled three. However, at times he is caring and helpful to others. He is extremely loyal to his friend Ikkaku, even going as far as to abandon his post at a pillar in the fake Karakura Town to try and save Ikkaku from being killed and threatening his allies who try to stop him. He cares deeply about what Ikkaku and Kenpachi think and hides the true nature of his Zanpakutō from them for fear of being hated. Despite his flamboyant nature, Yumichika can be an insightful person, able to quickly pick up on a person's nature and methods.