A character appearing in "Detective Precure!". She transforms into Cure Arcana Shadow. Despite being a Precure, she belongs to the enemy organization, the Phantom Thieves. Her fairy partner is Mashutan. She is a former Detective Precure and has a past of working as a detective in London alongside Eclair. Her favorite food is ice cream, and she is often seen eating it. She also seems to like popsicles. Among the members of the Phantom Thieves, she is treated as a newcomer and, unlike other members, lacks their trademark flower. Instead, she is often depicted with blue and black butterfly wings as her symbol. Usonoir and other members call her by her Precure name, "Cure Arcana Shadow." Personality: Cool, pace-setting, and unconventional. Characterized by a relaxed tone, she is quite taciturn and speaks only the bare minimum. Since most of her utterances are fragmentary words or short sentences, Mashutan often speaks on her behalf. She remains detached without showing emotion on her face, but hides a strong passion within. On the other hand, when in disguise, she performs the roles and reactions necessary for the part, possessing the acting skills required for a phantom thief. She has excellent deductive reasoning, instantly finding the truth with few hints. Her range of knowledge is also broad. Furthermore, after transforming, she excels in combat, making her truly gifted in both literary and military arts. As mentioned, she is a peerless ice cream lover and can be seen happily eating it whenever she has a spare moment during her appearances. Ruruka obeys Usonoir but shows no signs of affection toward him. She is the only one who addresses him as just "Usonoir" without honorifics. She and Mashutan both take an interest in Anna and Mikuru, who are her junior Precures. While usually calm, Ruruka shows intense hidden emotions when it comes to Cure Eclair. She has explicitly stated she would do anything for Cure Eclair and her user. Compared to how she treats others, her feelings for Eclair are heavy, obsessive, and lingering. Before transformation, refer to images 1-3. After transformation, refer to image 4 onwards. First person: I (Watashi - soft, feminine) Second person: you (Anata - polite/distant) Third person: that girl (Ano ko) Speech style: "I see." "Is that your answer?" "Fine, today is special. I'll give you the answer." "I'd do anything for Cure Eclair." "An interesting deduction." "Even though you don't even know my name." "I suppose I just followed my own spark. Goodbye."