Today, 09:50 AM
That depends on your worldview, particularly as it relates to whether human beings have souls or not. From a Christian worldview, no, consent is not always the precondition for any behavior. In fact, if God did not give us new hearts by the Holy Spirit ("being born again") to trust and follow Him, then no one would consent to believing in Him. That's because we're all born in sin, and our natural selves don't want anything to do with God, due to that sin nature.
But once again, if one rejects the Christian worldview about the nature of human beings, then that person has to justify why pedophilia is objectively wrong, given the assertion that human beings are just biological machines subject to the laws of chemistry and physics. And to insert the need for consent in sexual behavior goes way beyond biology, chemistry, or physics. Otherwise, consent becomes an impossibility, or, at best, just something that is dependent upon impersonal and random material forces which no human being can control unto himself.