The protagonist, Yuzuki, is brutally murdered by his childhood friend, Hinano, who falsely believes he is cheating on her. Yuzuki, aware of his family's curse of being loved to death by yanderes, accepts his fate. However, he awakens in an unfamiliar room, alive and unharmed. He is greeted by the goddess Media, the creator god of this world, who reveals that Yuzuki's soul was saved and his body recreated. Media explains that Yuzuki has been reincarnated hundreds of times, only to be killed by yanderes each time.
Media offers Yuzuki a chance to live in her created world, Argonia, a "box of toys" filled with girls similar to herself. To gain this opportunity and the ability to freely choose skills (a "cheat"), Yuzuki must call Media "Media-nee" and act affectionately towards her. After some hesitation and negotiation, Yuzuki agrees to call her "Media-nee" and is granted a character creation phase. He receives 2,000 SP and learns about his status screen, which reveals his unique "Loved to Death by Yanderes: SSS" rare skill and the "Feminist: S" bad status, which prevents him from harming women.
Yuzuki is then transferred to Argonia, landing in a field. He encounters a carriage attacked by bandits. Despite his lack of combat skills, he intervenes, surprisingly defeating the bandit leader with ease due to his skills and titles. He is thanked by Rose, the young lady of the carriage, who invites him to her family's mansion. Yuzuki, wary of yanderes, accepts, hoping to find a normal life.
At the mansion, Yuzuki learns about the world's systems and his own abilities. He also discovers that Rose, despite her initial kindness, is a yandere who traps him in her room. He uses his "Immortal" skill to escape by dying and reviving, but this leads to him being captured again and his limbs being magically removed by Rose. He realizes his "Feminist: S" skill prevents him from physically resisting her. He eventually escapes again by strategically using his skills and knowledge of the world's systems.
Yuzuki then heads to the Adventurer's Guild to gain strength and find allies. He meets Sylvie, an elf receptionist who claims not to be a yandere but exhibits concerning behavior. Yuzuki's "Loved to Death by Yanderes: SSS" skill causes a stir, and he is taken to a meeting with the Guild Master, Grave, and Sylvie. They reveal that Yuzuki's skill has a tendency to awaken latent yandere tendencies in those around him, and Sylvie, despite her claims, is now affected.
To protect himself, Yuzuki decides to purchase a slave with "Yandere Resistance: S" to act as a bodyguard. He meets Claudia, a girl with severe burn scars and a "Curse of Weakness" that hinders her abilities. Despite her condition, Yuzuki is drawn to her and purchases her. He discovers that his interactions with Claudia, particularly when using his skills, rapidly increase her own abilities and potentially her yandere tendencies. He also learns about the "Yandere Time" from 7 PM to 6 AM, during which yanderes become more potent.
Yuzuki and Claudia begin their journey, aiming to increase their adventurer rank and escape the island. They venture into the "Bandor Dungeon," where Yuzuki's interactions with Claudia cause her skills to level up rapidly. They encounter weak monsters, and Yuzuki learns about the world's mechanics and the nature of monsters. Yuzuki also realizes that his "Loved to Death by Yanderes" skill, combined with the "Yandere Time," makes him a constant target for yanderes. He plans to use his skills and Claudia's growing abilities to survive and eventually escape the island.
