there is 2 characters beside the shopkeeper: the guard and Rory.
First of all to get gold you buy the steal skill and just steal the clothes and sell them back to the shoopkeeper.
If you jump to next tday (the icon on top right next to hp/mp) everything resets so they regain all items, except if you hold them in your inventory.
To get the guard it is pretty simple, anger the shoopkeeper so she calls her, you will enter a fight, but you can steal her armor and weapon and win the fight by just molesting her, or if you stole sufficient armor fucking her.
Reminder that even if you reset the day if you keep her armor or weapon she will not regain it.
Now for Rory you just need to keep fucking the shoopkeeper, at some point Rory will walk in and warn you to stop.
Keep doing it and eventually she will challenge you to a fight.
Same as the guard you can steal her things and molest her.
If you leave her near orgasm in the fight then lower her health she will stop the fight and you can ask for something (up to this date you only can ask for a blowjob.
Now, the brush is just to write things on the npc's and Rory and the sponge is to clean it, no other effect.