16-year-old super-studier Nagi Umino, second-year student at the Megurogawa Academy high school, was switched at birth. On his way to a dinner to meet his birth parents, he accidentally meets the brash, outspoken, Erika Amano, who is determined to make Nagi her fake boyfriend as she never wants to actually marry. But once Nagi makes it to dinner, he finds his parents have decided to resolve the hospital switch by conveniently having him marry the daughter his birth parents raised...who turns out to be none other than Erika herself!
It was just a usual morning.
Akira Shiroyanagi, a high schooler who loves games and Konpeito (Japanese sweets), has suddenly been dragged into a battlefield by a mysterious girl who calls herself Mion. The participants are told that they are "erased from the family register, involved in an experiment, and gained certain powers."
Akira is determined to win the game with his newfound powers and destroy the organization. Armed with a power no one expects and his "brain" skills, the new period of intelligence battle begins!
Mukai Naoya has loved Saki Saki since grade school, and when she finally accepts his feelings, he's at his happiest. But one day, a cute girl named Minase Nagisa confesses to him! Not wishing to choose only one over another, Naoya chooses to go out with both of them!! What will be of this love triangle that challenges morality itself?