TV-Series
Description
Kaori Hakase, who goes by Dr. Kaori, is a twelve-year-old self-proclaimed genius engineer specializing in Bottleman. Her name functions as a homophone for the Japanese word meaning "doctor" and is inspired by the soft drink Dr. Pepper. Diligent and highly intelligent, she frequently becomes overly absorbed in gathering data, a habit that sometimes leads her to infringe on others' rights. She is resourceful, playful, and often smug, taking pleasure in teasing those around her or boasting about her skills. Despite these traits, she remains a loyal friend, readily offering help to companions in need. A recurring feature of her behavior is her tendency to grow overexcited when presented with new information, which often results in distraction and occasional recklessness.

In appearance, Kaori possesses eyes with purple and pink hues and dark purple hair carrying a magenta tint. She wears dark eyeshadow and an earpiece on her left ear, which also displays a green heart-shaped earring. Her fingers are painted with green nail polish, and she wears a black choker around her neck. Her clothing includes a dark pink crop-top with white accents, layered over a dark purple strapped garment that features a heart-shaped trinket. She pairs this with black trousers decorated with a white belt and large white and pink pockets, finishing the outfit with black boots laced with green straps and green soles.

Kaori enters Bottleman battles through an initially rocky encounter with Cota, caused by her overzealous and obsessive approach to Bottleman research. They gradually become friends. She creates Docpepion DX for herself, a speed-type Bottleman bearing a Scorpio constellation motif, and supplies Cota with both a Speed Core and Control Core for Colamaru DX. She later assists in repairing Colamaru DX, managing only to return it to its base form before expressing surprise at its subsequent upgrade to Colamaru Energy DX. She allies with other BMA supporters to oppose B-DACT and Team Citrus and provides Tsubasa Akaushi with wing parts for Raidbrave DX. Eventually, she begins working under Machiko Hocari, whom she idolizes, and participates in a battle against Seimei Usami only to be eliminated due to overexcitement. She also develops special metal caps enabling Cota and Ryo to defeat the AI threat Blastboss, though she claims much of the credit from Professor Rootbeer. After the AI crisis concludes, she is seen cheering for Cota and Ryo among friends and rivals.

In side stories, Kaori is notably wanted at the BMA Museum for disassembling exhibited Bottleman, resulting in her being mandated to wear "excitement measurement" devices for surveillance. She later learns to detach these devices and fasten them onto the Black Suits, the museum's security personnel. On one occasion, she delivers an overview of C.C. Leon DX's backstory at the museum but becomes overexcited and tries to break exhibition cases, leading to her removal by the Black Suits. Another side story showcases her development process for Docpepion DX, demonstrating her use of a 3D printer to produce parts and enhance her Bottleman's rapid-firing capability. She underscores that Bottleman can be fabricated via 3D printers, though a warning is issued advising viewers not to attempt this themselves.

Prior to creating Docpepion DX, Kaori utilized two other Bottlemen: a power-type model colored in indigo, light yellow, and green, and a speed-type in violet, light blue, and red. Neither was officially named. Her development of Docpepion DX involved designing a trigger component to increase reload speed and firing rate, originally conceived for her violet generic Bottleman but eventually expanded into a complete Bottleman capable of performing single-handed rapid shots.