Consent must be FREE and CONSCIOUS. A person who is asleep or under duress is not consenting. Taking substances (alcohol, drugs, cannabis…) or even sexual energy and physical intimacy can also alter consciousness. So you need to be all the more vigilant if you use a psychoactive substance or interact with a person or persons in an altered state of consciousness.
All involved clearly understand what they are committing to by accepting the interaction. Consent must be informed.