Sometimes you don’t really want to hurt someone, but instead need to hold them tight and stop them from moving. Make either a Hard (TN 30) Physical Strength + Melee (Unarmed) or Physical Agility + Melee (Unarmed) roll. If successful, the defender is unable to move and may only struggle against their attacker. They may no longer make their own attacks or perform actions that require movement.
On subsequent rounds, the attacker may repeat the roll to maintain the grapple, opposed by the victim’s Physical Strength + Melee (Unarmed). For each round after the first the attacker receives a bonus +10 to the TN. For example, our hero has grappled a thief for 2 rounds already, so on the 3rd round he will receive +20 to the TN making it an Average (TN 50) roll.
Every round that the attacker is successful at grappling, they may choose to simply maintain the hold, or block their opponent’s airways and asphyxiate them. Follow the rules for asphyxiation if they choose to do this. Characters with fangs may make an unopposed bite attack instead.