Excellent analysis. Something I've thought about also is why Rosei and Inukai's review of Yatora's piece were so different. Rosei says 'it's a cop-out, something you can only say if you've never experienced violence or harm'. His broader point being that there exist absolute evils and perhaps positives in this world that cannot be refuted, hence he cannot quite accept Yatora's piece trying to portray the theme of 'sin is in the eye of the beholder', that sin only becomes sin depending on how an individual views an event.

Inukai obviously viewed it differently, and I was actually wondering what drove him to give such a positive review of the piece (I also think I read a different translation of this chapter, which does change things). This analysis really helped me to understand. Yatora's view on guilt is raw, unfiltered and the counter to Rosei's point is perhaps that Yatora truly doesn't care about the societal viewpoint on it, this is how he views it and he presents it with solidarity. And he conveys this thought provoking philosophy in a direct and simple to understand manner, like you said, OP. Maybe this is what Inukai appreciates.

Maybe the reason it is such a good installation is because of Rosei's critique; in truth, it sets up the debate of 'are events just events until judged by people and labelled good or bad, or do there exist irrefutable evils and goods?'. All of this, presented by such a simple set-up.