10 years passed and Koushiro had forgotten about his sister completely. He lives a normal life, working at a dating agency. However, his sister would be attending high school in the spring. To ease her daily commute, she moves in with Koushiro. This situation proves perplexing for him. To make matters more awkward, he had previously dated Nanoka without recognising her as his sister. To add to his embarassment, the agonies of a broken heart had once driven him to tears, and it was Nanoka who had comforted him.
Nanoka attaches herself to Koushiro as if to make up for the time lost during their separation. Koushiro decides to become a good brother, but fails from the start. Nanoka is just too cute, and he cannot help being aware that she was an attractive girl.
He knows he must hide his feelings for his sister. However, every time he
meets innocent Nanoka, those feelings surge to the fore and make him irritable, resulting in another day of self-loathing.
