What started as dinner at Darkness's mansion with Princess Iris has turned into Kazuma being dragged back to the castle! Rain explains the situation, and Kazuma agrees to keep Iris company. His wild stories leave the princess with stars in her eyes.

Kazuma thinks of a way to stay in the capital for Iris's sake, and declares that he will capture the thief who's causing a stir in the streets! Since the thief targets nobles with bad behavior, Kazuma and his friends decide to stay at Alderp's mansion.

Kazuma and the gang fail to defeat the hydra in the lake near Axel. The gang hopes to rely on knights from the capital, but they've been delayed due to a bandit disturbance for which a bounty has been issued. Darkness, however, is obsessed with the hydra.

Darkness's wedding to Aldarp is imminent. Despite Aqua's and Megumin's pleas, Kazuma has no intention of intervening. Vanir then visits the mansion and reveals a shocking secret to Kazuma.

Kazuma has crashed Darkness's wedding to Aldarp and pays him the two billion eris he says he's owed. Aqua and Kazuma try to make off with Darkness but Aldarp won't relinquish her so easily and orders his guards to stop their escape.