魔王

1. Origins, structure, and basic meaning

• Structure: 魔王, read まおう, is a title combining the supernatural or demonic 魔 with ruler 王.
• Basic usage: It names a powerful evil ruler in fiction or games, as in 魔王の城.

2. Common pitfalls and similar expressions

• Scope and context
  • 魔王 is usually a fictional title, unlike 国王, which denotes an ordinary national monarch.