"April 1st is the day when the world is full of lies, however to Kouta, it is his precious imouto’s birthday. His father returned that day after a long time away and told him: “Actually Kouta… you have 364 other imoutos”. He was still confused when his father brought him to Tachibana Gakuen. He was the only guy at the school. The other 365 students were… all his imoutos"
"After his father’s death, Jin was separated from his 365 imoutos and ended up living overseas. He told them to live ‘strongly’ until he comes back to them. Ten years later, he reunited with his imoutos in Japan… and they are all gang leaders!? Not only that, but it was said that the strongest imouto will become oniichan’s bride."