One of the dumbest moments in the story. They already know she's a liar. She's been prosecuted and everything. But now the author is playing up that spectacle by showing that the characters have shit for brains.
I mean, the 3 have never been shown as smart, rational thinkers to begin with. And it's justified. Ren and Itsuki are literal teenagers according to the wiki, and Motoyasu is in his early 20s, and clearly a bit cuckoo in his head - the guy literally got himself stabbed to death with his philandering. Anyway, most people
are dumb at that age, and have little idea how to properly manage their emotions, or the perspective how to understand them. And that's exactly what we see with Ren; a young guy who never faced hardship, who is still a child, now suddenly faced with a serious amount of survivors guilt.
Of course he is looking for someone else to blame. Otherwise he has to hate and loath himself. Most people can't even stand light amounts of self-criticism, so this?
Myne tells him exactly what he wants to hear, what
feels good, so he wants to trust her, despite what she did. Because the alternative is considering himself a bad person, in his own simplistic view. He doesn't know how to properly process shame or guilt, and Myne simply takes advantage of that weakness.
