That room is for use with the named NPCs that you unlock via the succubus girl's brainwashing, not the generated ones. You want to build a VIP room somewhere up there for anybody elseIs the private manor thing just completely broken? Whenever you drag an npc and the player into the same room, they both just vanish.
But yes it's janked up to hell and back. Even when you unlock the content in question, you have to wait for the entire sex scene to finish playing out before you can go back to the normal map or else the whole thing just resets