The Poor Little Cutie Is the Monsters’ Darling in the Infinite Flow World

Xu Xingyuan, a transmigrator in an Infinite Flow world, arrives at the Monster Apartment after his stepbrother replaces his bus ticket with a Death Ticket. The apartment is a lethal environment where employees are consumed by the residents if they break the rules. Despite the horror, Xu Xingyuan accepts his fate, finding comfort in the structure and care provided by the apartment's NPCs, including the snake-like Doctor, the masked Nun, and the sadistic Security Guard Berus. He maintains a stoic, obedient demeanor, sweeping floors and feeding the basement's man-eating Little Monsters while avoiding the forbidden Top Floor.

His routine is disrupted when a red yarn ball rolls down the stairs, luring him toward the Top Floor. The Nun intervenes, warning him that the entity residing there, known as That Lord, has taken an interest in him. Shortly after, his colleague Lin Zhe, driven mad by the apartment's pressure, pushes Xu Xingyuan into the monster pit during feeding time. Xu Xingyuan is swallowed by the Little Monsters but is spared when a noble black cat appears, commanding the beasts to submit. The cat reveals itself as the true form of That Lord, the core of the Infinite Flow world. Berus arrives with Lin Zhe's severed head as a gift, revealing he killed the traitor for attempting to kill Xu Xingyuan.

The Doctor discovers that Xu Xingyuan's blood stabilizes the black cat, who has been in a deep slumber for centuries due to a curse. Realizing Xu Xingyuan possesses a soul pure enough to withstand the corruption of dungeon environments, the Doctor proposes he become a Ferryman, a role responsible for transporting monsters between dungeons. Although the position is dangerous and currently understaffed, Xu Xingyuan agrees, seeking validation and purpose after a lifetime of being told he was a burden. The Doctor and Berus attempt to find a mentor, but the remaining Ferrymen are too busy or dead.

The black cat, whose human form is Gu Nian, decides to personally mentor Xu Xingyuan. Upon meeting Gu Nian, Xu Xingyuan is intimidated by his cold, aloof demeanor. During a private session in the infirmary, Gu Nian reveals his hunger and bites Xu Xingyuan's wrist, drinking his blood directly. The act leaves Xu Xingyuan unconscious and weak, but Gu Nian remains indifferent, viewing him merely as a food source. The Doctor scolds Gu Nian for his lack of control, but the entity remains unmoved.

Preparing for his first dungeon mission, Xu Xingyuan is shown a vast armory of S-Rank weapons by Berus, though he lacks the strength to wield most of them. The story concludes with Xu Xingyuan unaware of the full extent of his significance to Gu Nian, while Gu Nian begins to show subtle signs of attachment beyond mere sustenance. The dynamic between the frail human and the ancient, powerful entity sets the stage for their dangerous journey into the Infinite Flow dungeons.