Express consent is permission for something that is given specifically, either verbally or in writing. Express consent contrasts with implied consent, which is an assumption of permission that is inferred from actions on the part of the individual.
Like many other substances, binge drinking is often used as a coping mechanism for a person who is undergoing various forms of emotional stress/trauma. Any situation that could be stressful/traumatic for someone could cause them to binge drink, examples include; the ending of a relationship, financial struggles, poor mental health etc.