Yeah, I feel like his story was quite abbreviated in the anime. They tried to get across some of his story to help the viewer empathize, but there was still quite a bit cut. He was largely a victim of bad timing, poor communication, and then a very opportunistic Rona. IIRC, when he spent time training with Hibiki, they spent time talking about a future society in which the barriers between nobility and non-nobility were eroded and there was more equality in general. He also very much cared for Ruria and was very hurt when she tried to brush him aside, essentially ignoring or forgetting their shared past together (which was very meaningful to him).

Also iirc, Rona is in communication with him often as he is given stronger and stronger doses of the medicine. She amplifies his insecurities and stokes his hatred for Kuzunoha. This drives him to deeper depths of desperation, desiring more pills. It is a vicious cycle that ultimately leads to the events that we will see play out next episode.

At the end of the day, I don’t feel too bad for him. But, I do think that he was pretty well fleshed out for what essentially amounts to a minor antagonist. It’s a credit to the writing that he wasn’t simply some jerk looking for power like we so often see in the isekai/power fantasy genre.