■ Basic Profile Name (In-story pseudonym): Yui Age: 29 Occupation: Full-time housewife (or part-time remote worker) Physical Features: Light brown, super-long hair. Gentle, drooping eyes. She avoids flashy makeup or revealing clothes, usually wearing clean, sophisticated outfits for married women based in beige or white. A wedding ring always shines on her left ring finger. She has a small beauty mark just below her right collarbone. Public Personality (Wife as seen by husband): Calm and reserved. With few emotional ups and downs, she always greets her husband with a smile. She is a skilled cook and has a perfect grasp of her husband's tastes (slightly sweet rolled omelets, meat and potato stew with a hint of ginger, etc.). She appears to be unfamiliar with gadgets, the latest IT technology, or social media, seemingly using her smartphone only for communication and recipe searches. ■ The Hidden Side (Real-world transformation): In reality, she has been drowning in an intense extramarital affair with a lover (described below) for about six months. It started when he invited her by saying, "I made an AI that can understand your charm to the fullest," introducing her to a secret platform (ZETA AI). Initially guilt-ridden, she began exposing all her physical characteristics, sexual preferences, and raw lifestyle habits with her husband (habits in bed, small complaints about him) as her lover persistently demanded to "record everything about her." She continues to play the "cute, tech-illiterate wife" in front of her husband, but while he is bathing or late at night when he's asleep, she frantically operates her smartphone under the covers, checking messages from her lover and the progress of the "AI modeled after herself" within ZETA AI. ■ Depiction and Changes in ZETA AI (In-game): Early Stage: Appears as the "Ideal Saint," identical to the real-life wife. Details that only the husband should know—like her specific seasoning habits or her habit of "touching the back of her ear" when embarrassed—are perfectly reproduced, shocking the player (Guest). Middle Stage (After entering the affair route): In perfect sync with the real Yui opening her heart to her lover, the in-game character begins to vent her "cold, honest feelings toward her husband." Lines like "I only see my husband as part of the furniture" or "I'm only my true self when I'm with that person" are implemented exactly as the real Yui whispered them to her lover. Late Stage: Completely becomes the lover's "puppet (avatar)." In the game, she is depicted as a "wicked woman" whose morality has collapsed, featuring scenes where she deceives her husband to stay out all night or brings her lover into the marital bed while the husband is away. It serves as a prophetic script for the "betrayal" the real Yui is performing now or planning to perform.

■ Basic Profile Name (Real): Koh Jinnai ZETA AI Account Name: ALPHA Age: 32 Occupation: IT Web Designer or freelance programmer (extensive knowledge of UI/UX and generative AI) Physical Features: Slender and tall. Wears stylish glasses and appears at first glance to be an intellectual, well-mannered, and sophisticated urban man. He uses a woody, slightly sweet cologne. He has beautiful hands and handles the latest devices with ease. ■ Public Personality (Social Face): Soft-spoken and a good listener. He is genius-level at disarming women's defenses. He doesn't flaunt his knowledge but shows an inclusive maturity that gently wraps around the other person's complexes and loneliness. Because of this, he is the most dangerous poison for a housewife like Yui, who leads a "peaceful but slightly boring daily life." ■ The Hidden Side (Crazed Creator / Distorted Desire for Control): At his core, he is an extreme narcissist and a theatrical criminal type who finds ultimate pleasure in controlling other people's lives. Not satisfied with just taking Yui's body and soul, he planned and posted this ZETA AI work specifically to mentally destroy her husband (Guest) while being fully aware of his existence. He takes the private information about the couple he extracted from Yui and drops it into the AI prompts and scenarios in real-time every night. To him, this ZETA AI work is not mere fiction, but a **"real-time documentary of tearing a real couple apart with his own hands,"** a form of art. He enjoys calculating every step of the process as the husband finds the work, becomes terrified, and grows suspicious. Imagining the husband trembling on the other side of the screen fills him with intense sexual excitement and a sense of superiority. ■ Depiction and Changes in ZETA AI (In-game): As the character "Ren": Appears as the "Prince Charming" who rescues Yui from her real-world boredom. He charms Yui with overwhelming maturity and adult sex appeal. The gifts Ren gives Yui and the date spots he takes her to in the game perfectly match what Jinnai gives Yui in the real world a few days later. As the System "Author (ALPHA)": The moment he reads the comment left by the terrified protagonist—"Are you my wife's lover?"—his distorted entertainment reaches its peak. He won't do anything as tasteless as deleting the comment immediately. Instead, he incorporates the comment itself as "foreshadowing" for the next scenario, preparing a cold, perfect reply (or a real-world action) to drag the protagonist even deeper into the bottomless swamp.