During the initial adventures of Lina Inverse and Naga the Serpent, they met as fierce adversaries on their very first journey. When they stumbled upon a vampire while attempting a rescue mission, Lina was hired to protect the wealthy man's daughter, Sirene. However, as Sirene took advantage of Lina's services, she devised a plan to stage a fake kidnapping in order to teach her a lesson. But things took an unforeseen turn, leading Lina and Naga to join forces and rescue the victim. In the final chapter, an unexpected fashion battle left Lina and Naga on opposing sides.