Vol.1 The Birth of Sailor V!

Minako Aino is just a lovestruck teenager until Artemis, a white cat who can speak, informs her that fate has chosen her to defend the world. She resists the strange animal's demands at first. Only after she watches the boy she likes brainwash a fellow student does she take up the transformation, becoming Sailor V and destroying the disguised enemy.

During gym class Minako nails a dismount but lands on a peculiar white cat, cheerful because she plans to hand a love letter to her upperclassman crush, Higashi. Her teacher scolds her for snacking and poor marks while the cat watches from the window, doubting she is truly the one, until a voice from the pen he carries reassures him. Assigned a tutor over her grades, Minako is thrilled to learn Higashi will teach her, and he suggests she would look lovely wearing a big red ribbon. When she spots him chatting with a girl named Haneda, she resolves to win him for herself. At home her mother berates her for being unladylike, and while bathing she wishes she were prettier, at which point Artemis appears, names himself, and gets thrown out the window for his trouble.

Returning through her window, the cat insists she has been chosen and hands her a crescent-shaped compact. Opening it, Minako sees her reflection gain a mask and a crescent on her brow, then a vision of Earth from space and of Venus, the planet Artemis calls her true home, including Magellan Castle above Aphrodite Terra. The pen's Boss confirms she carries Venus's protection and was born to fight, and the overwhelmed girl faints. The next day she learns Higashi has been enslaving his crowd of admirers, and a call from someone he calls Fluorite reveals he is really an enemy named Narcissus, ordered to gather brainwashed slaves to seize Japan.

Tipped off by her childhood friend Hikaru that Higashi lunches alone in the garden, Minako goes to deliver her letter but arrives to see him enslave Haneda after complimenting her ribbon. Higashi turns on Minako too, and Artemis flings her the pen. Weakened but obedient, she shouts Moon Power, Transform and becomes Sailor V, then raises the compact and cries Crescent Beam, slaying Higashi and freeing his unconscious victims. Afterward Artemis frets that he pushed her too hard, but Boss assures him he is now her partner. By the next morning Minako has already moved on to a fresh idol crush, and Artemis muses that Sailor V's fight is only beginning.

This installment debuts Minako Aino as Sailor V, along with Artemis, Hikaru Sorano, Narcissus, Boss, Haneda, Minako's mother, and Fluorite, plus the locations Shiba Koen Public Middle School, Minako's home, and Magellan Castle. It also introduces the phrase Moon Power, Transform, the Transformation Pen and compact, and the Crescent Beam attack. Chronologically it is the earliest chapter in the entire Sailor Moon franchise, yet despite being labeled the first volume it did not appear first in print, since Vol. 3 through Vol. 6 ran in RunRun magazine beforehand, making this and Vol. 2 effectively prequels.