Kazuma and the gang receive a letter from Princess Iris. She wants to share a meal with them while hearing about their adventures. While Kazuma is giddy with wonderment of her beauty, Darkness is terrified of heads rolling in the event of any rudeness.

The Devil King's army attack alarm rings in the royal capital! The adventurer's guild calls on high-level adventurers to join the battle. Having failed to capture the thief at Alderp's mansion, Kazuma joins the fight in order to redeem his reputation.

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.