The night in the magic tower was so quiet. Plus, Oliver recently hired a few people to help Ursilla in the magic tower. They were assigned to cook food and serve Ursilla. The rest, they have nothing else to do.
For the safety and cleanliness of the tower, all is handled by Oliver, of course using his magic abilities. Ever since the magic tower was first established, Oliver had not hired anyone because he wanted so badly to hide his identity as a great wizard. Oliver preferred to be known as the owner of the Deadly Wind Guild.
However, since Ursilla's presence as his disciple, Oliver cannot apply his independent habits to Ursilla who is impossible to get used to his way of life. After all, if Oliver was caught giving Ursilla a miserable life, Victor would have had Oliver's neck cut off.