Mamoru...one of many names, but (almost) always a friend of the sailor scouts. He is Tuxedo Kamen, Tsukikage no Knight, and Endymion. Not to mention his earth name of Mamoru. As Tuxedo Kamen in Sailor Moon, he attacks with a red rose, a cane and his intelligence. All of the scouts have a crush on him. Then, near the end, they find out that he is Mamoru and Prince Endymion from the time of the Moon Kingdom, and that Usagi (Serena), known then as Princess Serenity, was the one he loved. In the first part of Sailor Moon R, during the Doom Tree series, he doesn't know of any of this except that he is Mamoru; he lost all of his memory at the end of Sailor Moon. His soul continues to fight, however, as Tsukikage no Knight, using a white rose.
He then, of course, regains his memory at the end of the Doom Tree series. Tuxedo Kamen has returned!!! And Usagi has a boyfriend...but not for long...
Poor Mamoru!! In the last season we barely see him. He is supposed to be studying in America at a university. But Sailor Galaxia got to him first. Usagi gets very depresses when he doesn't return her letters. She gets even more depressed near the end of the series when she finds out what happened to him.
Love Life: Well, it has basically been outlined above, although there is more. Before he remembered his past and realized that he was Tuxedo Kamen, he was dating Rei. Then he remembers his love with Usagi, and they are eventually together (No, Queen Beryl doesn't count since she brainwashed him). In the Sailor Moon R movie the villian seems to be in love with Mamoru, as well. And of course, everyone was in love with Tuxedo Mask before his identity was known. ^_-

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