Trom's entire final fight against Guitar, whom had previously almost annihilated the entire party a couple of volumes ago.
Sizer attacking Chestra.
Sizer: Don't you touch... MY RAIEL!
Clari defeating HELL KING BASS/Lute, who had previously been hyped as the strongest Mazoku despite NOT BEING A MAIN CHARACTER, and despite having both his arms and legs destroyed by him. Clari, you sir, are badass.
Flute, who was so far labelled as Butt Monkey and the Damsel in Distress is so furious with what Vocal, the guy even Sizer can't beat has done that she takes him by surprise and slaps him.Twice'. Not to mention the time she's stabbed by Mazoku!Hamel in the chest, but still stands up to take his hand and smile reassuringly.
Hamel turns into a mazoku completely and proceeds to trash his 'Dad'- while still keeping his consciousness.