Megumin's adorable little sister, Komekko, has arrived in Axel! Her fellow Crimson Magic Clan members Funifura and Dodonko are along for the ride as well, and before they know it, they wind up right in front of Kazuma's party. Komekko attempts to explain her situation, warning the group that the Demon King's daughter has launched an attack on the Crimson Magic Clan village! Unable to fight back with the rest of her clan, Komekko was forced to flee her home, which brings her to Kazuma...Another Crimson Magic Clan member sounds like the last thing his party needs, but can he really refuse her...?