Have you changed?

Xerdawn panted as he struggled up the steps of Twilight's View, his return to the Castle was far from enjoyable since he was stranded back in the Dark City & attacked by so many Heartless...but he'd made it back in one piece...more or less...
"Glad I got away from them..." he wheezed before finally stopping to rest against a banister, "Why do we not eliminate the Heartless back there for a change?"
"Hey, Xerdawn, you're back early," Roxas greeted him, "You finished your mission already?"
"Yeah, just did some recon today," Xerdawn chuckled, keeping himself from facing Roxas, "Can't believe Xaldin abandonned me, though...left me back in the city..."
"What? Why'd he do that?" Roxas asked.
"I dunno...he called it 'training'...but the Heartless didn't think of it that way..." he sighed in reply, heading off up the stairs, "Well, I'd best tell Saïx I'm back or I'll be up to my neck in punishment..."
"Wait, Xerdawn!" Roxas stepped forward to stop him.
"What is it?" Xerdawn finally faced his friend; Roxas gasped in shock at what he saw.
"What's with your...err..." Roxas couldn't describe it; Xerdawn's blue eyes had somehow changed colour & were now green.
"What?" Xerdawn asked, patting down his cheeks, "Something on my face?"
"Err...not quite..." Roxas was still lost for words.
"Well, tell me later, ok?" Xerdawn gave a quick grin before heading up the stairs to the Grey Area, hoping Saïx was still there.
'That was weird...Roxas thought to himself, 'I swear his eyes used to be blue...' but he then shook the thought from his head, 'Must be imagining things...' He eventually followed Xerdawn up the stairs to the Grey Area, "Wonder if Axel & Xion are back yet..."


What could've happened to Xerdawn for his eyes to change colour if they were blue before?

Roxas, Organization XIII & Kingdom Hearts (C) Tetsuya Nomura/Square Enix
Xerdawn & art belong to me