Okay Guild Master but if you knew this place had a dungeon you damn kusogaki-lolibaba, you should have already anonymously purchased the property and roped it off from potentially being taken in by civilians who would then have their lives at risk. No alarms would've been raised over the dungeon as everyone just thought it was a stygmatized property already so it being roped off wouldn't draw any untoward attention. As it stands, get the hell out and come back with a warrant and legal document because you're trespassing and abusing your authority. But of course the MC is a bit of a pushover.
Also, still holding unto the idea of connecting his dungeon to the shop right after the guild master just stated they were appropriating that dungeon currently in the shop is stupid. You are actively thinking of placing your dungeon entrance near a different dungeon entrance that is actively known by the guild master and will be actively explored by the guild. You are literally risking your secret home by thinking of placing it right next to a heavily investigated dungeon hole.
And accept the compensation. She broke your damn floor, you have no need to repair the thing she broke after she invaded your legally rented location. If anything the property owner should be sending bills for damages straight to the guild and if the guild does not comply and decides to act like a mob boss, then you as a former hero should not associate with them. Then again you own a slave so, I guess your morals is a bit on the grey side. So long as you're consistent, fine, but at least grow a spine and a pair.
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Side note. Brave of the MC to just shove his big wood into the core's mouth like that and forcing it to swallow it all whole.