Virvatuli is Kissa's owner and she doesn't bite the hand that feeds her. Virvatuli adopted Kissa after Aida's death.
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Kissa was originally Aida's kitten. She wanted to give her a perfect name, but didn't have time to figure it out before her untimely death. That's why Virvis never really named her either, and she's just kissa.
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Even though Änri was/is a quiet kid, who doesn't bully or bother her, for some reason Kissa seems to hate her.
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