Himiko is a very cheerful girl, to the point of smiling even after having presumably killed someone, displaying sadistic tendencies. This continues even when danger is imminent, as shown when Tomura Shigaraki was about to attack her, but it tends to stop when she is bored or annoyed. Himiko is frequently seen blushing seemingly out of excitement rather than embarrassment, giving her a permanent look of what appears to be lovesickness on her face. However, she has shown that she can easily be embarrassed, such as when she thinks people are coming on to her, or when she is naked when copying clothes of the people she has transformed into. Himiko is obviously mentally unstable and has a very twisted perception of love and friendship. This is evidenced when, despite her attempting to kill Ochaco Uraraka and Tsuyu Asui, she tries to befriend the two girls as they fight, affectionately calling Tsuyu by her first name and describing the former as "lovely".