TV-Series
Description
Eiko Oni, a student at Babyls Demon School, transitions from a first-year in Class A to a second-year, marked by her distinctive appearance: long, frizzy blonde hair with uneven bangs, bull-like horns, pointed ears, and the standard uniform accentuated by a red bow and cat-eye clasp. Her hair ties shift between blue and red, reflecting the hues of those she admires, while a camera remains a constant companion for capturing moments tied to her passions.

Shy and polite around her idols, Eiko balances this reserved exterior with quiet resilience and determination when faced with challenges. Daydreaming often distracts her, causing missed chances to connect directly with others, yet her inherent kindness drives actions like crafting meticulous study guides to aid peers.

Her admiration for Iruma Suzuki sparks after he saves her in a duel, later extending to Ameri Azazel following another rescue. Though unreciprocated, these feelings fuel her desire to impress both. She shares a steadfast friendship with Gaako, a growing bond with Alice Asmodeus through mutual support of Iruma, and familial ties with her younger brother Eita, who joins Babyls.

Academically advancing from rank Aleph to Bet, Eiko excels in organization, stealth, and gathering information. During the Harvest Festival, her strategic hiding secures 666 survival points. Despite frequent daydream-induced lapses—like spacing out near Iruma or skipping events he attends—her admiration remains unwavering.

In spin-offs such as the *If Mafia AU*, Eiko thrives as an undercover journalist, leveraging a pivotal image of Iruma to ascend professionally. Bonus manga chapters spotlight her comedic endeavors, often centering on attempts to engage Iruma or Ameri, punctuated by a recurring gag where her fervent "hunting" for Iruma-related content lands her in mischief.

Eiko’s undisclosed family bloodline magic and focus on self-improvement anchor her background, culminating in a tenth-place class ranking. Across narratives, she evolves as a figure of comedic mishaps and quiet tenacity, embodying the duality of a dedicated admirer and a resourceful student.