Keisuke started working this year and is satisfied with his life, since he found a job in his desired field, even though it’s for a small company. However, despite the motivation and satisfaction of living alone for the first time, he did feel a bit tired from it and wondered if he should find a girlfriend.
Then one day, his imouto Riho came to his place. Their parents had come down with the norovirus, so they suggested that she stay over at his place temporarily while studying for her exams. She had always liked him as more than just her older brother and now that they were living under the same roof, that feeling started to become even stronger. At the same time, he also was charmed by her and viewed her as a girl.