Chiba Mamoru / Tuxedo Kamen
Japanese Name: Chiba Mamoru
English Name: Darien Shields
Birthday: August 3
Identity(ies): Prince Endymion, Tuxedo Kamen, Tsukikage no Knight (Moonlight Knight), Neo-King Endymion
First Episode: Episode #, ""
When he was very young, Mamoru was in a horrible car crash when his parent's car plunged off the side of a cliff. His parents were killed and he was orphaned and left with no memory of his past. He was sent to an orphanage, where he lived until he was old enough to receive a job and provide for himself. Mamoru is a loner and has few friends, even after he and Usagi become a couple. His best friend is Furuhata Motoki, the guy who runs the arcade that Usagi and her friends love to frequent.
He spends most of the first season and the first arc of Sailor Moon R trying to figure out who he really is. In the beginning, he transforms unsubconsciously, but he slowly begins to realize what is happening and fully embraces his role as Usagi's protector, Tuxedo Kamen. He always appears just in the nick of time to save the Sailor Senshi from whatever evil they're battling, and throws a rose (sometimes more than one) to stun the enemy so that Sailor Moon can finish them off.
In Sailor Moon R, Mamoru had a brief stint as Tsukikage no Knight (the Moonlight Knight), who was really an "essence of his soul" (SSP) and rejoined with Mamoru after he recovered his memories yet again (everyone's memories were wiped by Usagi after the final showdown between her and Queen Beryl.)
He also has another identity as Prince Endymion. Long ago, during the Silver Millennium, Mamoru was the Prince of the Earth and was deeply in love with Princess Serenity of the Moon Kingdom, even though their relationship was forbidden. During the fierce final battle between the dark forces and the Moon Kingdom, he rejected Queen Beryl's advancesl in order to protect Serenity. In the ensuing battle, both of them were killed and in a last desperate attempt by the Princess's mother, Queen Serenity, they were sent sent along with the other princesses to the future on Earth, where they were reborn years later on without any memory of their past in the Silver Millennium.
In the manga he also rejected Queen Beryl for the same purpose. Angered by his rebuffal, Beryl used the power of the Negaverse to destroy the Moon Kingdom and formed a dark alliance with Metallia, an entity even more power hungry than her. Before Endymion goes to fight, he and Serenity share a final kiss. He is killed trying to defend the moon and his lover. Princess Serenity was so grief stricken by his death that she took his sword and commited suicide so they could always be together.