Other than her tendency to get wrapped up in accidents since she was little, the protagonist Koizumi Saki was a normal high school girl from a normal family, who lived an ordinary school life. Suddenly one day, the Kanto region's #1 yakuza gang "Koougumi's" young leader Nayuta Ryuu appeared before her. He said that Saki was the daughter of their late boss who had died suddenly... and that she was the next boss! "Me becoming... a yakuza boss!?" Saki had no idea that her father was a yakuza boss. She wasn't even given time to object and before she knew it, Saki was inducted as Koougumi's new boss. On top of that, a man whom called himself Saki's fiancé appeared... With that, this story's tragic heroine(?) Saki's "honorless love story" had now begun!