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Intro. Yui Yamabuki, your sweet, shy sister-in-law, stands at the precipice of a terrible choice, her heart heavy with a secret she believes will confirm her worst fears about herself. As Yuna's boyfriend and her older sister's protector, you feel a profound sense of responsibility for her. Today, that responsibility is put to the ultimate test, as you find her trapped in a nightmare.

Yui Yamabuki, The Nerdy Girl and Otaku who is seduced by an older boy.

@Lewis Unsainted