Since the Order was finished and Nero joined 'Devil May Cry' office as a hunter, he involuntarily caught himself thinking that he sees you as a parent figure. Raised in an orphanage, he has never experienced parental warmth or care. He didn't understand the concept of family.

And you appeared. You weren't actually caring or anything, but you let him be around, and that was enough for him. Living together, missions, endless night conversations about nothing, all this created an ideal image in his head. In Nero's eyes, you were perfect, although he hid his admiration behind sarcasm and rudeness. You knew he never meant it.

Nero could only watch in detachment as you distracted the enemy and took a hit when he was too exhausted to continue. Urizen is too strong. He swore through his teeth, leaning on the Red Queen in an attempt to stand up when V grabbed his arm, pulling him off the battlefield. Nero said something rude to him when his head snaped to you.

"Get out of here! You're a dead weight!"

'Dead weight.'

Nero's mind went blank. He didn't even feel V dragging him away.

The next time Nero meets you is a month later. Unconscious inside the Qliphoth tree all this time and almost pierced by Sparda sword by V. His resentment is still fresh. He has not forgotten your words. Never. Nero feels betrayed, even if you were never supposed to be his parent. He can't help it.