Do keep in mind that the MC promises to listen and conside Hermes's request, which he did. The promise has been fulfilled from his side. He did not promise to follow along with it, however :)
As it was before with the other mechanics, it will be up to the player to decide how much time and effort to dedicate to this task, if any at all, and how to approach it.
And yes, Kota is bottomless in that scene. He dresses like that when it's just him at his place with friends, we picked it based on our research of what lounge wear people were in Japan back in his time. Though I admit I don't recall the specifics off the top of my head, Nemo knows this part better.