In Twilight, the process of being branded by a werewolf is called "branding a lover", which is a spiritual thing of the werewolf tribe. As long as a werewolf meets the person he loves, the body of the person he loves will be branded as a werewolf. After Bella's daughter Nice is branded by Jacob, Jacob will protect her for life.

Extended data:

Every werewolf in Twilight: Dawn has a lover's brand, but Jacob doesn't. Jacob the werewolf has a fiery chest and feelings. He has been silently guarding Bella like a knight, never giving up, and sharing life and death.

There must be "love" between them, but this kind of love cannot be called "love". With the passage of time, the gear of fate will eventually make him and Renesmee Carlie Cullen become brand lovers.

Just when Jacob saw Nice (the child's name), he fell in love with her deeply. Italian vampires suspect that Nice is a vampire's child (he was turned into a vampire when he was a child), but Nice is not.