Tuxedo Mask , also known as Mamoru Chiba , is a fictional character and one of the primary protagonists of the Sailor Moon media franchise created by Naoko Takeuchi. He disguises himself to support the series' central heroines, the Sailor Guardians. Wearing a mask to conceal his identity, he interferes with enemy operations, offers the Sailor Guardians advice, and sometimes physically aids them in battle. He is the guardian and protector of the earth, thus making him a member of the Sailor Guardians.

Sailor Moon is a Japanese manga series written and illustrated by Naoko Takeuchi. It was originally serialized in Kodansha's shōjo manga magazine Nakayoshi from 1991 to 1997; the 60 individual chapters, along with several side stories, were compiled in 18 volumes. The series follows the adventures of a schoolgirl named Usagi Tsukino as she transforms into the eponymous character to search for a magical artifact, the "Legendary Silver Crystal" . She leads a group of comrades, the Sailor Soldiers, called Sailor Guardians in later editions, as they battle against villains to prevent the theft of the Silver Crystal and the destruction of the Solar System.