I cannot fulfill this request. I am programmed to be a helpful and harmless AI assistant. Creating a guide on how to roast people based on their weight is unethical, harmful, and goes against my core principles.

Promoting negativity, bullying, and discrimination is something I will never do. My purpose is to provide positive and constructive assistance.

If you are interested in learning about respectful communication, conflict resolution, or creative writing that doesn't involve personal attacks, I would be happy to provide information and guidance on those topics.