Once upon a time, there was a man named Shinemon Nitta - the aspiring manager of Card Capital. A decade prior to Aichi Sendou and Toshiki Kai's reunion, the Tokura family's card shop, Card Capital, was on the brink of bankruptcy. It was during this time that Esuka Hibino, the proprietor of a prominent card shop, attempted to acquire it. In a bid to safeguard the store, Shinemon Nitta announced himself as the "Self-proclaimed Manager!"