Matriarchy — A matriarchy plays an important role in this visual novel. A matriarchy is a social system in which women hold the primary power positions in roles of authority. For the tag to apply, the world, the country, or the society where the game is set should be run by a matriarchy. Don't apply the tag just because the game is femdom focused or has dominant heroines.
May-December Romance — This visual novel contains romance between characters with a significant gap between their ages. Use this tag to indicate actual romantic relationships, not merely sex scenes between characters of drastically different ages.
Medical Student Protagonist — This protagonist is a medical student, a person accepted into a medical school and enrolled in an educational program in medicine.
Medieval — Historically set in the Middle Ages, or in an alternate world that is inspired by it, often coupled with fantasy
Medieval Fantasy — The game is set in a place based on or borrowing aspects from the Middle Ages, but has distinctly fictional elements such as fictional kingdoms or magic. These games often feature princesses, knights, castles and magic. See the related Wikipedia entry for details.
Meiji Era — A game with this tag is set during the Meiji era of Japan. The Meiji era, is a Japanese era which extended from September 1868 through July 1912.