Sdde-231 Sauna Lady Occupation -azumi Nagasawa- Guide

I should check if this is a well-known game or a lesser-known one. Maybe it's part of a series. I know that there are adult games with sauna themes, but not sure about this specific one. The user probably wants information or a character analysis, but since the input is about a game, perhaps the user is looking for a detailed character profile or some backstory.