You didn't want to get distracted by the box shaped objects on the table, because you don't want to question them while Professor Kao was explaining them. Rick however, was getting impatient as he just tapped his feet on the ground, and crossing his arms. Professor Kao was putting his book down, just before talking.
"What's the hold up, Gramps," Rick says. "I want to see what the BeastMon look like." "Rick, not now," Kao explains. "I'm trying to remember what I needed to say." You both give the Professor time to remember his words, as he was rubbing his hair. "Ah yes, now I remember," Kao explains. "Today is the day that I give both of you a BeastMon. When I was your age I found the BeastMon to be fascinating creatures of how they interact with each other, but alas I am too old to study them forward."
You then see Professor Kao go over to the box shaped objects on the desk next to you. "That is why I only studied three that are the only ones left of their kind in this country," Kao explains. "They are all in these Beast-Cubes. Using a Beast-Cube helps with making sure your BeastMon is loyal, and doesn't wander off on its own. Now Lucy, since you almost endangered yourself from going outside of town on your own, I'll let you choose first." "Wait Gramps, why does she get one first?" Rick asks. "You need to learn to have manners, boy," Kao explains. "I swear you're just like your father. Oh, before you can choose, I need to show you what BeastMon are in these Beast-Cubes."