Prelude to an Explosion of Madness
While Megumin was going to school, Komekko had befriended a demon named Host who has been working to break the seal imprisoning the Dark God Wolbach. It's during one of her visits that she found Ink and took her home. In the present, Megumin searches her house but doesn't find Komekko. Monsters then attack and kidnap Ink, only for Komekko to confront them to try and take Ink back. Megumin considers using her skill points to learn magic to fight the monsters, but hesitates as that would mean delaying her plans to learn explosion magic. Seeing Megumin's dilemma, Yunyun takes it upon herself to use her skill points to learn intermediate magic and fight the monsters, rescuing Ink. However, she uses up most of her energy in the process and collapses. At that moment the horde of monsters begins to head towards them, and Megumin realizes that Ink is actually the Dark God they are looking for. She also realizes she has gathered enough skill points to learn explosion magic, which she uses to destroy the entire monster horde. Afterwards, since they have both learned magic, Megumin and Yunyun graduate early. Megumin decides to officially make Ink her familiar and renames her Chomusuke.