non-negotiable (adjective)

1. In Greek mythology, the power of love is considered non-negotiable.

2. The curse placed on the haunted house was non-negotiable, and no one could escape its terrifying effects.

3. In the distant future, there is an advanced civilization where happiness is a non-negotiable condition for existence.

4. The superhero's vow to protect innocent lives is non-negotiable, and he never compromises on his principles.