There it was again, the new Cloud, the one Shinra would have been spitting teeth over losing if they'd known what sort of talent had escaped their grasp. Zack had seen some of that potential in Cloud when they'd first met, back before either of them understood how corrupt Shinra really was. Zack felt a little like he should snap off a salute and say "yes sir", but managed instead to say, "You got it," with a grin.
The Welcome Center wasn't bad, but staying with Cloud held more appeal. How could it not? Cloud was Zack's best friend. There would be no hiding, no explaining, no awkward hello's in the hall.