Ah! Who Does Big Sister Belong To?

Skuld's been spending a lot of time with Belldandy, but Belldandy still wants to go to school with Keiichi. Skuld decides to take apart Keiichi's bike, but ends up upgrading it. Megumi notices the upgrades and starts to critique it. This upsets Skuld, who issues Megumi a mechanic's challenge. At the suggestion of Keiichi's senpais, Skuld and Megumi enter a robot battle contest to settle their conflicts.