Dante's argument against Vergil about ruling humanity:
Vergil: Humans are frail, they're like children, they need our protection. Not just from others, but from themselves! We - you and I - have saved them.
Dante: You and I have saved them?
Vergil: Who else?
Dante: A human.
Vergil: Kat was useful but -
Dante: Kat saved my life, Kat held out under torture to keep your existence a secret! Kat led us through the tower to Mundus' lair. We would've failed twenty times over if it wasn't for her!
Kat begging Dante to spare Vergil's life, in spite of his ambitions and cold treatment towards her. Dante even looks somewhat relieved afterward.
Kat: I know who you are. You are Dante. Nothing more, and nothing less.
Dante carefully and patiently lending Kat an arm to help her walk to where they can better see the aftermath of the battle. His obvious protectiveness and affection is nearly a complete reversal from how dismissive and harsh he originally was with her, and how comfortable she is with accepting his help really speaks to her trust in him.