Darien is Serena's love of her life. At first, she hated him, but when she found out his true identity as her crush Tuxedo Mask, and even better, her long lost Prince Darien from the Moon, all was better. Tuxedo Mask helps the scouts fight, when Tuxedo Mask was not in use, the Moon Light Knight was. Arien was reincarnated from Prince Darien of the Earth back in the time of the Silver Milenium. Before going out with Serena, Darien dated Raye.
Luna is Serena's mystical black cat, who was also one of Queen Serenity's cat advisor. Luna is the one who taught the scouts everything they know, and always has "feelings" about whether or not something is valid or a NegaVerse scam. Luna is very harsh on Serena, although she probably doesn't mean to be.