Hogwarts: The Alchemist's Cage for Squibs

After transmigrating to Hogwarts, he becomes the least popular person there: Argus Filch, the Squib caretaker.

Abandoned by the wizarding world the moment he graduates at seventeen, he suffers humiliation and despair in the gap between the Muggle and wizarding worlds. To survive, the young "Filch" has to set aside his pride as a transmigrator and beg the wise Dumbledore in the most pathetic, hysterical manner for the chance to sweep the floors of Hogwarts Castle.

From then on, the "Squib Filch," petty, obsessive, and pathologically hateful of rule-breakers, becomes the perfect disguise he needs to survive.

Decades of lying low wear away his hope, leaving only numbness. Then the boy with a lightning-shaped scar on his forehead steps into the castle, and his long-delayed golden finger finally arrives!

The Rule-Breaker Capture System activates! Can he grow stronger by catching mischievous young wizards? No. The System doesn't grant him the power to wield a wand, but leads him down a unique path for a Squib: alchemy and rune forging! Knowledge floods his mind, and a faint glow shimmers at his fingertips.

But he knows that exposure means destruction. His identity as a Squib is both his best camouflage and his heaviest shackle.

And so, in the shadows of Hogwarts, an unknown master alchemist emerges.

He still angrily catches Harry and his two friends sneaking around at night, confiscates contraband, and curses rule-breakers with the vilest language.

Yet in the dead of night, the caretaker's office, piled high with "junk," becomes the starting point of a secret workshop. In the perilous depths of the Forbidden Forest, an exploring elf searches for rare materials for him; on ancient walls, he carves protective runes...