I haven't made a dedicated effort to show this (sorry!), but every character's name is a pun... in Japanese. Some are more obvious than others, but I thought I'd take the time here to actively list them all.
[ul]Harry (ハーリ): Obviously an actual name, but also a pun on ハリネズミ (harinezumi, hedgehog)[/ul]
[ul]Garu (ガル): this is an onomatopoeia for growling, typically from an animal like a wolf[/ul]
[ul]Peta (ペタ): a pun on both ペンギン (pengin, penguin) and ピーター (pītā, Peter)[/ul]
[ul]Kamu (カム): a pun on カブ (kabu, cub)[/ul]
[ul]Kurumi (くるみ): it literally translates to walnut, but it's more likely a pun on くるみ割り人形 (kurumiwariningyō, nutcracker)[/ul]
[ul]Jack (ジャック): derived from 孔雀 (kujaku, peacock) and possibly alsoピーコック (pīkokku, peacock)[/ul]
...I'm going to hope I haven't forgotten anyone.