Janicula, Grisilde's father, is the poorest of all the poor folk in Salucia, but life has blessed him with a virtuous daughter who cares for him tenderly. And Janicula returns that tender feeling.
When Walter does Janicula the honor of asking for his daughter's hand in marriage, he tells him that he imagines Janicula desires this as much as he does. Janicula confirms it: "Lord," he says, "my willynge / Is as ye wole, ne ayeyns youre likynge / I wol no thyng, ye be my lord so deere" (319-321). In this, Janicula reveals himself to be the perfect vassal, obedient in all things.
But Janicula's feelings upon Grisilde's return to his cottage show a more complex side of Janicula's character: he has always expected that Grisilde's marriage would end badly, thinking that "whan the lord fulfild hadde his corage" he would "voyden hir as soone as evere he myghte" (907, 910). This formerly hidden perspective of Janicula reveals his worldly cynicism as well as the indignities that he, as a poor man and vassal, must endure. With no choice but to obey Walter, he must yield his beloved daughter to what he is sure will be a sorry fate. One of Janicula's roles in the story, then, is to emphasize the powerlessness of the poor.