From Tokyopop:
When friends and loved ones begin to disappear, his sense of reality begins to crumble - until the day he runs into a mysterious figure who can erase a person's very existence...
KAZUMI Yuana
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From Storm in Heaven:
Yamada Hana's just moved to Tokyo, and her perfect debut falls disastrously flat. Not only do things at school start off badly, but her demon sister's sold her off to work for Haru, who seems to spend way too much time touching girls. If that wasn't enough, Haru's gorgeous, and Hana has a strange condition where she breaks out in hives whenever cute guys…