With one species of spiders down, Alros prepared himself, as his next target would be much difficult. And to release the would be stress that would no doubt will be cause by the hunt, he decided to enjoy himself.
Which is why he is sitting on his bed, waiting for his women to change into a more appropriate clothes. By appropriate, he meant lewd and erotic of course.
All of the clothes he left for them are that kind, though it varied in skin coverage, lewdness, and the types. From swimsuits to the cosplay one, to the one really meant to be used for private occasion, he had left it all.
But now, he wanted them to wear one specific clothing for the night. So, they all changed, taking their time to wear it. But he did not mind, because the result would be delightful.