Fans of Sailor Moon know that the manga's main character, Usagi Tsukino, is highly inspired by Sailor V. What they may not know is that Sailor V actually has her OWN manga series, which actually came out BEFORE Sailor Moon did. This manga is called Codename: Sailor V.
Sailor Moon first began publishing in December of 1991 and finished its run in Kodansha's Nakayoshi magazine in 1997. It was created by Naoko Takeuchi. The manga would eventually be adapted into an anime series. Over time it would become one of the most popular manga and anime series for global audiences. Sailor Moon was reworked from a previous manga, which also found its way into the manga - and the show - through mentions and light references.
Codename: Sailor V was also created by Naoko Takeuchi. It began releasing in August of 1991 and was a predecessor to its sequel series. The main character is Minako Aino, who takes up the mantle of Sailor V. It ran up through 1997, just like Sailor Moon, though it only had fifteen chapters compared to Sailor Moon's sixty acts. Minako was later re-envisioned as Sailor Venus in Sailor Moon. While the series are very similar, there are some distinct differences.
Sailor Moon usually works with her fellow Pretty Guardians to fight against the Dark Kingdom, the Black Moon Clan, the Deathbusters, Dead Moon Circus, and Shadow Galactica. Sailor V works alone and fights against the Dark Agency. Like fans will recognize from Sailor Moon, Sailor V's life changes when she meets a cat. This is a white cat with a crescent moon, named Artemis, who takes the role of Luna in Minako's life. However, Artemis DOES appear in Sailor Moon when she and Sailor Venus - her main companion - join the Guardians in their fight against evil. Like Sailor Moon, Sailor V also has a mysterious romantic interest, who goes by the codename of Phantom Ace, though the trajectory their relationship takes is very different from the one her counterpart has with Tuxedo Mask.
Early in Sailor Moon, Usagi sees reports of Sailor V saving people and there are various media that include Sailor V. After school, Usagi goes to a local arcade and plays a Sailor V video game, which she gets her friend Ami (Sailor Mercury) into. Codename: Sailor V has never had the same popularity as Sailor Moon, largely due to the sequel series being the one that received an anime adaptation. It was also a longer, more complex story than its predecessor. Nonetheless, Codename: Sailor V is an important part of Sailor Moon's history. In its secondary publications and re-issues, it has been compiled into two volumes. However, it is usually published in conjunction with Sailor Moon.
Fans have had debates regarding if Codename: Sailor V is canon - and if so, to what extent? Some fans have perceived it as a draft of the sequel series. Most fans' introduction to the series is through Sailor Moon, which has resulted in Codename: Sailor V being left to the wayside for the most part. Since it is usually published alongside Sailor Moon, the creator and publishers treat the two as a package deal that belong together. Due to its connectivity to the series as a whole (as well as the numerous parallels between the two), fans of Sailor Moon should definitely make it a point to read the Codename: Sailor V manga.