"Why would you do this?" DiZ demanded, intending for it to come out as a musing, analytical question, but his diction betrayed his quiet fury as surely as the face before his gaze had betrayed him.
Riku returned his stare with Xehanort's cool amber eyes.
"You hate him, too," DiZ wanted to mutter, accusingly, like the bitter old man he was becoming, but the last of his scholarly reserve held that vitriol momentarily in check.
Xehanort's face contorted into a severe frown, nonetheless. "Do you think I want to wear the face of the person who used my body to hurt my friends? That, after everything I've done to separate myself from that failure, I would casually go back to this?" Riku challenged, gesturing to indicate that mutually loathed aspect.
"Then why?" he demanded, feeling the oldness overtake the bitterness, tiredness dulling his anger into something hollow.
That familiar, dark expression lifted, just a little. "...Even if I have to see this face in the mirror every day for the rest of my life, even if I have to hate myself with every breath I take, if this can help me save Sora, then it's worth it."
There was an emotion written there on Xehanort's well known face that DiZ was sure was completely foreign to it. Whereas Xehanort had worn a thin cloak of Light around his Darkness, Riku wore a cloak of Darkness around a blazing Light.
"Do you truly care so much?"
"If I didn't, then what would be the point of even having a Heart? I'd be no better than a Nobody."
Oh, how DiZ hated that voice, hated that face. But somewhere more wrenchingly, he hated that Heartbecause it alone held the power to make him, wise man among wise men, feel ashamed.
How far from the path have I fallen, that I can stand next to Xehanort's form and be cast into shadow by his Light?
He'd grown comfortable, stewing in his aging rancor and slow vengeance, but now DiZ regretted pushing Riku so hard to defeat Roxas, regretted driving him to a sacrifice that had become a punishment for them both. Most of all, though, he regretted the reminder of what his Heart was for, because now that he'd seen it, he found he couldn't stop wishing that Xehanort had been capable of making an expression like that.
Then, because that hope was absurd, he laughed. He laughed because beneath all the heavy, twisted foundations of his rage, buried but never excised, remained the wish that he'd realized the dangers of his research sooner, that his apprentices hadn't all been lost to him. They betrayed me long ago. Why must I still care so much?
Riku had already given him the answer: Because I'm not a Nobody, of course.