Futaba's Palace is a unique location in Persona 5 Royal for a number of reasons. There's no hint of Tokyo in the surrounding area, Futaba was hurt by corrupt adults rather than being one herself, and she invites the Phantom Thieves to steal her Treasure personally. The Tomb also combines two of the Deadly Sins, Wrath and Sloth, since Madarame's Vanity isn't one of the usual seven.