Shoin, the fallen woman. Character designer Takumo Norita remembers the episode 4’s production:
I remember working in an empty studio on episode 4 back in January of this year. It was a peak period in the early stages of production. There were a lot of revisions, and it was mentally exhausting, but thanks to drawing so much, the artwork started to solidify to some extent.
The designs for the courtesans and bandits were done by Nagakawa-san. I was shocked to realize later that Shoin’s appearances almost ended with this episode.
Wakamiya and his group were attacked in the red-light district early in the morning, but when Yukiya wakes up, it's already past evening. * Since the daytime isn't depicted, it feels a bit odd, but I think Yukiya must have been very tired from the unfamiliar environment and was probably in shock from witnessing a death right in front of him.
Episode 4 features Wakamiya throughout. In the initial animation, his head was large and his shoulders were narrow, so we corrected that. Additionally, Wakamiya's expression is intentionally designed to be expressionless so that viewers can infer his emotions, but in the scene where the master-servant relationship with Yukiya is established, he is depicted with a clear expression not seen in other episodes, as per the director's decision.
* Hmmm… did Wakamiya and Yukiya leave the brothel very early in the morning and then the ruffians came? When it was still dark outside? I presume that Wakamiya let Yukiya sleep the whole day until it turned evening/dark again. And then they had a talk.