Unexpectedly we get lore of the Koma sword and Suguro's father. With Rin being thrown into isolation, his execution became something closer to reality that his classmates has to grasp. Shiemi's struggle while understandable isn't something I personally sympathize since I find it a bit selfish for her to focus on her own hurt without considering how hurtful her actions are to RIn, especially when she admits of having still cared about her.