A childhood "blood pact with Satan" has no power over someone who trusts in Christ — the cross cancels all such claims

Mike takes the question seriously without mocking it. His answer: whatever claims Satan might have had are completely cancelled by the blood of Jesus on the cross. Christ broke the power of Satan at the cross, purchased humanity back from sin and Satan, and anyone who puts faith in Christ receives all the benefits of that salvation. Satan telling this person they cannot be saved is a "death rattle" — the opposite of reality. In Christ, a person is a new creation; all things are made new.