Episode 15 has Julio stealing kirakiral from Miku, who is a very ill girl who constantly stays at the hospital, and that day was one of the very few times she was stable. Also, Miku is Akira's little sister, who she loves more than anything and hurting anyone (not just Miku but her friends, her family and an innocent) is Akira's Berserk Button.
Julio's flashback as Pikario in Episode 22 can be this. Especially when we see Noir forcefully removing the kirakiral from Pikario's body. It almost looks like he's ripping the fairy's heart out.
Episode 23 has Ciel having a mental breakdown. And when Ichika and Julio enter her heart, we see her with Dull Eyes of Unhappiness and with a sad and slightly twisted smile. The music doesn't help, that's for certain.
Yukari's visit in her heart in Episode 29. Especially when her younger self gives a Slasher Smile. It should be noted that it was no illusion and Yukari was exploring her heart for real.
Elisio alone is this. All of his dirty tactics revolve around way excessive Break Them by Talking (the one he pulls on Miku is particularly heavy). And his dead stare and empty smile are just the cherry on the cake.
