It says in the book that She caught up to Cleon as the pages were filing into their first practice of the day, and thrust his archery glove into his face. "Very good," he said, taking it. "You know, we all thought you wouldn't last this long." Kel stared at him, thinking, What an odd thing to say! "Last this long today, or last this long for five weeks?" she asked. "In training. You know." He spread his arms, taking in their surroundings. "Everyone had bets on that you'd run home before a week was up." He shook his head, smiling. "You might want to run now, while you still have the strength. Lord Wyldon will never let you stay." "He might surprise you," Kel retorted, keeping her face Yamani-smooth.
67 Cleon smiled oddly. "He never surprises anyone." He sauntered into the yard.
I think that Cleon is friends with Kel because they talk alot and they have casual conversations such as like telling what they're first impressions were like, and what they thought about each other. If Joren was Cleon I think that Joren wouldn't even be talking to Kel except for making her do errands.