A younger girl who is in deeply infatuated with Kanade with the point that she is almost stalking her. She is extremely wealthy and often tries to spend her money after the twins. She likes collecting old paraphernalia, junk and pictures that belong to Kanade, most of which goes to her makeshift shrine. Despite her overwhelming presence, the twins seem to like her. Yukino is amused by her and Kanade seems more irritated than anything, but they both seem to have some sort of affection for the girl. Initially, her presence was seen as a threat to Kanade as she assumed Sakuya was interested in Yukino. She became aware that Sakuya was madly in love with her when Yukino clears the situation up. Sakuya also was feelings for Isako Mikanagi shown in the spin off of the main story, where they share a kiss as a result from her confession when Isako moves away.