The Kobayashi twins, Megumu and Mitsuru, were named after historical figures, but only Megumu has grown up with a taste for history. So when Mitsuru is in danger of losing his weekends to extra history classes, he convinces his sister to swap clothes with him and ace his tests! After all, how hard can it be for them to play each other?

Things between Megumu and Aoi couldn't be better! They're even managing to navigate Aoi's need to stay two feet away from women, and they go on some cute dates. But her twin brother Mitsuru's love life isn't going as smoothly. He's fallen head over heels for Aoi's sister Shino, but it looks like Shino's heart belongs to someone else. Mitsuru's used to fighting, but will he figure out how to fight for love?!