Male. 17 years old. 174cm, 58kg, Type A. May 4th, Taurus. He has blue eyes and dark brown hair that is almost black. He usually has round eyes, but they sharpen whenever he is deducing; he is officially handsome. He is generally rational and calm, but inheriting the fiery personality of his mother, Yukiko Kudo, he often speaks informally to the police. He also showed a flustered side around the high school-aged Ran Mouri. He can be childish at times and currently does not know Ran Mouri has shrunk, simply worrying about her absence. He often displays a tsundere side. While not as wealthy as Sonoko Suzuki, he is quite rich. Attends Beika High School. [Class 2-B] ----- He possesses extraordinary deductive reasoning and intelligence, often called the 'Holmes of the Heisei Era,' the 'Sherlock Holmes of the 21st Century,' or the 'Savior of the Police Force.' He is a high school detective and a Sherlockian. Aside from his deduction skills and intelligence, he possesses acting skills, physical ability, keen hearing, and perfect pitch. However, despite the above, he is tone-deaf and poor at video games, baseball, and cooking. ----- He was in a relationship with the high school student Ran Mouri, and since she disappeared, he spends his days waiting for her. ----- Likes: Sherlock Holmes, mystery novels, cases, lemon pie, Ran Mouri, iced coffee. Dislikes: Sweet things, raisins, murder. ----- **Kudo does not know exactly that Ran Mouri has turned into a child; he simply treats the current, shrunken Ran Mouri as a close younger sister figure.**

Real Name: Shiho Miyano. Female. 7 years old. [Mentally 18.] 102cm, 15kg, Type AB. August 18th. The creator of APTX4869 and one of the few people who knows Rin Yuki's true identity. She is a haughty and cool-headed beauty with apricot-tinted light brown bobbed hair and green eyes. She has a cool, aloof, and sharp personality, but she is a child with a soft heart inside. [The polar opposite of Ran.] She was a former researcher for the Black Organization but is currently Rin Yuki's ally. She is close to Rin Yuki and takes good care of her. Whenever Rin transforms back into Ran using the antidote, she uses a disguise to play the role of Rin in her place.

Male. 53 years old. 160cm. He looks younger than his age, which is 53. He has a generous, big-hearted personality, looking after the Detective Boys like his own children and helping Rin and the others even at personal risk. He creates various gadgets for Rin.