Does the wife's consent become obligatory if the husband wishes to masturbate with her hand or with his own hand at his request?

A wife's obedience to her husband is among the greatest duties. She must obey him in matters of enjoyment unless she has an excuse, or he requests something forbidden, or something that would harm her physically or psychologically. If she is harmed by it, then obedience is not obligatory, based on the Prophet's (peace be upon him) saying: "There shall be no harm nor reciprocating harm." It is appropriate to be content with natural, permissible enjoyment, and the foundation of the marital relationship is compassion, understanding, and affection.