In a BDSM relationship based on dominance and submission, consensual non-consent means that the submissive partner agrees to submit to the authority of the dominant partner on a long-term basis. This authority includes the top's right to discipline the bottom even if such punishment is against the will of the bottom at the time it is given.
This type of consent is also called blanket consent or metaconsent. The submissive wants to be in a relationship where they are subjected to "emotionally real", non-consensual punishments. The concept of consensual non-consent allows partners to act out the ideal of a non-consensual power exchange without giving up the safe, sane and consensual principle.