Natsume Kiroemon, the protagonist, is the 45th leader of the Natsume family, and inherit the "Kiryuu no Mimi ", a tool which gives its bearer easy access to wealth and women. As a result of his father's death, he leaves the Italian monastery where he'd been training and rightfully takes the name "Natsume Kiroemon" as well as the power of the "Kiryuu no Mimi". Upon his return to Japan, he falls fatally in love with Kanako, one of the members of the rival Mina family. However, the evil hand of the Mina family attacks Natsume constantly and abductes Kanako. Now Natsume has unlocked the seal, making the Kiryuu's power surge, and he's striking back at the Mina family