Belldandy and Keiichi sit at their kotatsu while Keiichi bemoans the fact that they are nearly flat broke and it will be some time before his parents send more money. Belldandy tells him not to worry as she will handle the problem. She can’t make money, but she does cast a spell to allow them to somehow be provided with the needed funds. Immediately upon the completion of the spell, Keiichi’s younger sister Megumi appears at their home.

Keiichi is not pleased by this visit, but Megumi is impressed that Keiichi is living with such a beautiful foreigner. As Keiichi begins to get worked up over Megumi’s visit, she calms him down by handing him an envelope with several thousand yen in it. She’d mailed it to Keiichi but since he didn't tell them his new address, it got returned. So, Megumi brought it with her. The money was to help cover rent since she was planning on staying with Keiichi while she takes her college entrance exams.

This news disturbs Keiichi since he fears that Megumi will learn that Belldandy is a goddess. So he’s now determined to make sure Megumi passes her exams and thus is out of his house. So he and Belldandy ask if Megumi needs any help. She says she knows the material, but there is one bonus question she hasn't been able to answer. Keiichi attempts to solve the problem and after a long time, still can’t get the answer. Megumi shows the problem to Belldandy who solves it in seconds. Megumi is stunned because not only is the answer right, but it had taken her 20 minutes to get the answer. She doesn't let Belldandy know that she really didn't need help solving the problem. She instead brings Belldandy problem after problem in an attempt to stump her. Belldandy answers every question and solves every problem with ease. In the meantime, Keiichi still hasn't solved the first problem.

The next morning before Megumi goes to take the exam, she asks Belldandy what her and Keiichi’s plan for the future is. Belldandy responds by saying that she is on Earth only for Keiichi and that she will be with him until death parts them. This response surprises Megumi as she considers it old fashioned.

Megumi gets ready to leave for the exam site when Keiichi comes in having finally solved the problem from the night before. Sadly his answer is wrong.

At the exam site, Megumi develops a case of nerves, but Belldandy is able to calm her down with a spell through Megumi’s watch. Megumi passes her exams for entrance into the last college Keiichi was expecting – Nekomi Tech!