OVA
Description
B-ko Daitokuji, heiress of the wealthy Daitokuji family and an honors student at Graviton High School, possesses a tall, slender frame with long blue hair curling at the ends and gray eyes. She maintains a public facade of calm poise, showing respect to authority figures like teachers, yet privately exhibits haughtiness and obsessive tendencies toward her objectives. Her primary fixation involves winning the affection of C-ko Kotobuki from her rival, A-ko Magami, manifesting as elaborate schemes to undermine A-ko. However, the rivalry often overshadows genuine interest in C-ko.

This obsession traces to childhood flashbacks depicting B-ko as an "ugly little girl" with a "basin haircut, piggy eyes, and dumpy legs" who bullied C-ko—potentially an immature expression of affection. As B-ko matured, this dynamic evolved into romantic desire, though she rationalizes it as wanting to be C-ko's "best friend." Her wealth enables extraordinary capabilities; she designs and constructs advanced mecha overnight, like the Akagiyama-23, to combat A-ko’s superhuman abilities. She also demonstrates exceptional physical resilience, lifting spider tanks and enduring A-ko’s full-powered kicks, even matching her unarmored in "Cinderella Rhapsody."

During "Cinderella Rhapsody," B-ko’s rivalry escalates when A-ko develops a crush on motorcyclist Kei Yuki. Though driven more by competition than genuine attraction, B-ko pursues Kei, leading to a chaotic confrontation at the Alpha Cygnans' Space Hotel. This triggers a citywide evacuation and mobilizes Graviton City’s Public Works Defense Force. Kei’s rejection—revealing his love for C-ko—leaves B-ko disappointed alongside A-ko.

In other media, her antagonism toward A-ko and fixation on C-ko persist. "Project A-ko 2: Plot of the Daitokuji Financial Group" showcases her repairing an alien ship overnight. The alternate-continuity OVA "A-ko the Versus" (internationally "Uncivil Wars") reimagines her as a 21-year-old bounty hunter partnered with A-ko on a desert planet. Here, she lacks romantic interest in C-ko, instead showing attraction to male villain Gail, with her and A-ko as "Vitriolic Best Buds."

B-ko’s intellect and resourcefulness contrast with emotional immaturity, as her schemes frequently escalate to city-destroying battles. She embodies the "Academic Alpha Bitch" trope, her ego driving conflict, yet she occasionally reveals vulnerability when thwarted. Her development consistently highlights wealth-fueled ingenuity, competitiveness, and an enduring, distorted fixation on C-ko.