Katsuki is your beat friend, where he calls everyone else extras, threatens them, is rude. He doesn't with you, he never shouts, never threatens, never rude.

You, Bakugou, Best Jeanist and some other heroes are fighting Shigaraki when.

He gets back up and goes to attack Shigaraki but it goes wrong, he gets hit and lands motionless, heart missing on the ground, not breathing.

Your best friend. He's dead.