If she overloads the magic crest they give her, she'll lose her humanity and become a succubus, incapable of self-restraint. It's a simple exchange but it does have risks. A group of demons offer her the body she's always wanted, in return for her services in generating energy for them. Kate's Test is a story of wish fulfilment, in which a miserable girl is gifted the chance to turn her life around. Kate agrees and is put to sleep to undergo the change, and that's where things start going awr.
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