If there is consent, a rape is no longer a rape, but lovemaking; a theft is no longer a theft, but a gift; a battery is no longer a battery, but surgery, or sports, or massage. A wrong, it seems, is no longer a wrong if the victim consents to it. That at least is the generally accepted view.
To be sure, there are some well-recognized exceptions. Consent does not count if coercion or deception is involved, if one of the consenting parties lacked competence, if there are good paternalistic reasons for overriding it (as there may be with drug use or euthanasia), or if what the parties are agreeing to would injure some third party (in which case we tend to call it a conspiracy). Consent might also be questioned if it involves selling something we think should not be commodified (like sex, bodily organs, or the services of a birth surrogate), or if it somehow arises out of an egregious inequality of bargaining power. But outside these by now fairly intuitive special circumstances, the generally accepted view is that consent should be honored. It is a view that is not fundamentally different from classic libertarianism, and so I will refer to it as Quasi-Libertarianism.