Chapter 1 - The Melancholy of Mako-chan

Juken Sensou Hen 1 - Mako-chan no Yuuutsu (translation: "Exam Battle 1 - Mako-chan's Depression" (or "The Melancholy of Makoto") was a side story originally published in the magazine, RunRun, and the first of the three Exam Battle stories. It was published in Volume 13 of the manga.

Plot
Instead of studying, Makoto wanders into a store that has opened near the school which is having an amazing sale. As it turns out, the store is possesed by Touhi-chan, an ancient genius loci (a place's protective spirit), who has infused the food and drink in the store with her own evil power to bewitch the customers. After Makoto falls into the spirit's trap, she transforms into Sailor Jupiter and destroys the spirit with Jupiter Coconut Cyclone.

Trivia

 * Makoto's fear of airplanes is explained in this chapter. The reason she is afraid is because her parents died in a plane crash, causing her to become afraid. The anime version of Makoto is shown not to have this fear, as in episode 188, she boarded a plane without fear.
 * As part of the 2015 birthday celebration week for Usagi, a special livestream event on Niconico was held and featured the Japanese voice cast of Sailor Moon Crystal performing a read through of this chapter, playing their respective characters.

Melancholia Mako-chan