Serika Kurusugawa, eldest daughter of the affluent Kurusugawa conglomerate dynasty, wields quiet influence over her family’s sprawling empire in electronics, automotive manufacturing, and robotics—notably overseeing projects involving the humanoid robots Multi and Serio. Her status as heiress empowers decisive actions, such as bypassing security systems at a Kurusugawa-operated amusement park to aid friends infiltrating restricted zones.

Reserved and habitually withdrawn, she communicates sparingly, often lost in occult studies or silent contemplation. Her murmuring speech frequently forces others, especially classmate Hiroyuki Fujita, to reiterate her words aloud. As the solitary founder and curator of her school’s Occult Research Club, she dedicates herself to witchcraft and black magic, meticulously gathering arcane components like lizard tails for ritual use.

Long dark blue hair frames her pale complexion and piercing blue eyes, typically adorned with a witch hat, flowing cloak, and sailor-style uniform. Though predominantly distant, she intermittently engages in mundane pursuits like swimming or part-time work, subtle contradictions to her enigmatic persona.

In the OVA *Remember My Memories*, her latent resolve surfaces as she manipulates familial clout to covertly assist Hiroyuki and allies, balancing her detached disposition with strategic pragmatism. Her younger sister Ayaka, a spirited martial artist, contrasts her mystique, yet their sibling dynamic remains cordial. Documented portrayals consistently anchor her in occult obsession, subdued authority, and an inscrutable, introverted nature, without deviation from these core traits.