Damage Your Opponent: While grappling, you can deal damage to your opponent equivalent to an unarmed strike. Make an opposed grapple check in place of an attack. If you win, you deal nonlethal damage as normal for your unarmed strike (1d3 points for Medium attackers or 1d2 points for Small attackers, plus Strength modifiers). If you want to deal lethal damage, you take a –4 penalty on your grapple check.
How does this work for creatures with natural weapons?
How does this work for creatures with natural weapons?