Sesshouin Kiara (Swimsuit Mooncancer) is a swimsuit variant of the Beast III/R from Fate/Grand Order, classified as Moon Cancer class. A nun-like figure embodying the human evil of lust, she transforms into a demonic bodhisattva using her unique skill. In this form, she appears in a revealing swimsuit, wielding powers to absorb and slaughter Servants as energy sources. Originally introverted and passive with deep compassion, her Beast nature drives her to seek salvation through carnal desires, separating and manipulating Alter Egos like BB, Passion Lip, and Meltlilith.