Hanabusa, Sumireko

英純恋子

The daughter of a conglomerate CEO and the final student to transfer into Class Black. She is wealthy enough to supply her own furniture for the classroom, yet she does not intend to cause anyone inconvenience. Notably, she shares the same eyes as Tokaku. While she is considerably warmer toward people than Tokaku, hints suggest she is one of the more dangerous members of Class Black.
She deliberately waited until all other assassins (except Nio) had completed their attempts before beginning her own, as her wish was to prove her strength by killing Haru herself. She and Haru are the only students aware of Class Black's true intention.

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She appears considerably colder in the anime than in the manga, particularly when she gives Banba's unconscious body her Flower Motif as a sign of her expulsion and leaves—an attitude more pronounced than Isuke's. Her speech and mannerisms are much more formal.

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