Location from My Hero Academia by Kohei Horikoshi
The underground fortress of Overhaul's yakuza organization. A labyrinthine complex beneath an estate where Eri was held captive and the quirk-erasing bullets were manufactured from her body. The heroes' raid here was one of the most intense rescue operations in the series.
The compound is a place of hidden cruelty. Above ground it maintains the fiction of a declining yakuza family. Below, Overhaul conducted his experiments on Eri — disassembling and reassembling her body to harvest the material for quirk-erasing bullets. The heroes' raid turned the underground into a running battle as Overhaul's lieutenants reshaped corridors to separate and trap the rescue team. The deeper you went, the worse it got.
On the surface, a traditional Japanese compound with tile roofs and wooden gates — the facade of an old yakuza family estate. Below, the complex sprawls into an industrial underground maze of reinforced corridors, laboratories, and sealed chambers. Walls shift and reshape thanks to yakuza members with structural quirks. Sterile labs contrast with crumbling stone tunnels.
Also known as: Shie Hassaikai Compound, Hassaikai Base, Overhaul's Base