:::WARNING SPOILERS::: Konatsu is Kohanamaru’s twin brother. He is very popular at his school, because of his looks, athletics, and smarts. He is also the boy Nanao has a crush on. Konatsu is the only one in his family who cannot switch, but he is also the only one who can return the partners back to normal when they are unable to do it themselves. It is believed that Konatsu did not inherit the ability because of his twin brother, remaining the reason of Konatsu’s jealousy towards Kohanamaru Konatsu is a part of a love triangle between Nanao and Kohanamaru, out of jealousy towards his brother for being able to switch, Konatsu tries to steal Nanao away from Kohanamaru, making him Kohanamaru’s rival for Nanao’s affection. Konatsu later teams up with a girl named Madoka Shishihara, after she threatens him and mentions her interest in Kohanamaru. At the end of volume 2, Nanao reveals that Konatsu for sometime had been planning to move to America and had done so. He later returns and reappears in chapter thirteen. Though Konatsu’s personality appears cold and distant, he truly cares for Nanao not just to make Kohanamaru jealous, and he also cares for Kohanamaru a lot as well. (from Wikipedia)