Yumichika Ayasegawa is a lifelong friend of Ikkaku Madarame. He values Ikkaku's opinion very highly and tends to follow him everywhere. The two joined the Soul Reapers so that they could serve under Kenpachi Zaraki. Since Ikkaku took the 3rd seat position, Yumichika settled for 5th Seat, thinking that five looks almost like a three, which he believes to be the most beautiful number. He has colorful feathers on his eyelashes and eyebrow as well as shiny skin and hair, giving him a rather womanly appearance. Narcissistic and vain, Yumichika judges everyone and everything by beauty. He goes so far as to try to forget things he deems "ugly" after seeing them and even tries fighting an ugly opponent with his eyes closed.