Ansem the Wise was a famous scientist and sage-king of Radiant Garden. To protect his people from the darkness, he and his apprentices performed research and experiments to study the heart, which resulted in the creation of the Heartless. Eventually, Ansem's apprentices were taken over by the darkness, and, when he decided to end the research, they banished him to the Realm of Darkness and Xehanort continued the research in his name.
Alice is a shy, quiet high-schooler who recently moved to Tokyo from a town in Hokkaid�, which she misses for its peace and lack of pollution. When we first meet Alice she is being teased and mocked by the boy next door, Rin Kobayashi. She retains Mokuren's ability to talk to plants, and make plants grow by singing to them. Despite Rin's encouragement, Alice is having a hard time remembering her life as a scientist. This is because she is afraid of losing current herself in Mokuren's memories and also because she feels that she, as Alice, could never live up to the others' expectations of Mokuren. This refusal on Alice's part to continue her moon dreaming comes to a head when she decides to stop joining the other reincarnates for their after school meetings, and instead joins the school choir. At this point even the other reincarnates begin doubting that she is the reincarnation of Mokuren, especially given that she has only had one moon dream. (Source: Wikipedia)
A moon rabbit, she came to Gensokyo about 30 years ago to escape a war between the Earth and the Moon. Since then, she has been an apprentice to Eirin, a pet to Kaguya, and a caretaker to Tewi. She has the power to drive people mad with her eyes — mainly in the form of hallucinations — as well as communicate telepathically with her kind. She also has control over waves of all kinds, such as light waves, brainwaves, and electromagnetic waves. "Udongein" and "Inaba" are both nicknames, the first given her by Eirin and the second Kaguya; the latter is what Kaguya calls all rabbits. (Source: Wikipedia)
Ryutaros (リュウタãƒã‚¹) is the fourth Imagin that gives Ryotaro his power, which allows for the transformation into Den-O Gun Form. His natural weapon as an Imagin is a shotgun named the Ryuvolver (リュウボルãƒ�ー). Though he is the last Imagin to appear, Ryutaros initially possessed Ryotaro the moment that Urataros did, and simply hid himself from the others. Ryutaros reveals himself in his form when he is attracted by Naomi's coffee inside the DenLiner. Ryutaros is most childish in personality with a love for drawing and animals. Ryutaros also appears to enjoy break dancing, to the point to that it is incorporated into his flashy fighting style. His personality is one of a fun-loving dancer/disc jockey and is the most dominant Den-O has. This recklessness also causes the most collateral damage, as he fires his gun aimlessly. When he possesses Ryotaro, he first asks "Is it okay if…?" (…ã�„ã�„?, …Ii?, usually "Is it okay if I beat you up?" or "Is it okay if I end it?") followed by "Your answer doesn't matter" (ç”ã�ˆã�¯è�žã�„ã�¦ã�ªã�„, Kotae wa kiitenai).He has the ability to control people simply by snapping his fingers. This tactic works with summoning the Machine DenBird as well. Originally, Ryutaros possesses Ryotaro after being promised the title of become the DenLiner's conductor by Kai, who also gives the Imagin a ticket, on the condition that he destroys Ryotaro. However, because he does not wish for Airi to cry, Ryutaros decides not to destroy Ryotaro. The only individual he will listen to is Airi, whom he affectionately calls "sis" (ã�Šå§‰ã�¡ã‚ƒã‚“, onee-chan, Ryotaro only calls her the more formal "sister" (姉ã�•ã‚“, nee-san)). Because he knows that Airi has loved Yuto Sakurai, and from faulty advice on love from Kintaros, he becomes jealous of Yuto and wishes to show that he is stronger than him. But when Kai takes matters in his own hands in killing him, combined with realizing how he and Airi can not to be together, Ryutaros matures a bit to cope with fading away while eventually mustering courage to fight in the final battle against Kai. He usually refers to Urataros, Kintaros, Sieg, Teddy respectively as "Turtle-chan" (カメã�¡ã‚ƒã‚“, Kame-chan), "Bear-chan" (クマã�¡ã‚ƒã‚“, Kuma-chan), "Bird-san" (トリã�•ã‚“, Tori-san), and "Blue Bear-chan" (é�’クマã�¡ã‚ƒã‚“, Aoikuma-chan). However, he excludes Momotaros as he is not based on an animal and Momotaros does not understand him like the others do. He is referred to by the others as "Ryuta" (リュウタ, RyÅ«ta?). After this initial arrival on the DenLiner, he is rarely seen without a pair of headphones over his head. One of the TarÅ�s, Ryutaros's basis is unclear as early promotional material stated his form to be based on the legend of Tatsu no KotarÅ� (Taro the Dragon Boy) while TV Asahi's website for Den-O states that his form is based on Ryotaro's mental image of dragons. One of the Imagin Anime shorts discusses Ryutaros's possible namesake.
Kintaros is the physically strongest of the Imagin that are linked to Ryotaro and speaks Kansai-ben. He originally possessed a man named Masaru Honj�, but joins Ryotaro when Den-O is unable to defeat the Rhino Imagin. He is mostly found sleeping on the DenLiner, but will possess Ryotaro whenever he hears someone say anything resembling "cry" (泣�る� nakeru de). As Den-O, he lives up to his namesake and fights with an axe as Axe Form, has primary control of the left arm in Climax Form, and his power is tapped in the DenKamen Sword's KinAx mode.
After taking good care of her health and living for a long time, Tewi became something more than an ordinary rabbit. She leads the Earthborn rabbits living in Eientei. Her impetuous temperament makes her seem more like a fairy than a phantom. Humans who lose their way in the bamboo forest around Eientei sometimes catch a glimpse of Tewi. Those who see her are able to find their way out without fail, so she is considered a guide of the forest. It's a shame that they waste the fortune given to them by Tewi on such a small thing, but humans are too clueless to notice their mistake. (Source: Touhou Wikia)
A witch who has settled down in the Scarlet Devil Mansion. Unlike the mistress of the house, she is not weak against sunlight; however, she does not go out much. She spends her days in a library where the sunlight cannot reach. This is so that the books won't be damaged, but the unhealthy atmosphere is bad for her health. She doesn't have a very proactive personality, but rather always walks her own path. However, she is always interested where knowledge is concerned and will proactively go and try to acquire it. She completely depends on her books, but still makes a lot of mistakes. Although she is quite skillful, her complete lack of physical fighting ability can't be helped. She pretty much never attempts to directly punch or kick her opponent. She makes up for this with her knowledge of a great variety of powerful magic. She's more at ease using magic than trying to attack physically. Dividing the magic she uses according to the days of the week is a secret hobby of hers, but no one has realized this. (Source: TouhouWiki)