The only creature for whom Quasimodo felt any affection was Claude Frollo. The archdeacon had raised and sheltered the hunchback and had made him the bell ringer and for this Quasimodo's affection and obedience never wavered despite Frollo's often harsh and severe manner. After Quasimodo became deaf the priest had worked out a series of signs for communication so that it was only Cluade Frollo with whom Quasimodo could have any intercourse. The archdeacon held complete sway over the hunchback who would have willingly thrown himself from the tower had Frollo demanded it.
The Hunchback of Notre-Dame: Novel Summary: Book IV Chapter 4