Coin Knight (ディスクナイト?) is a demon in the series.
Knight of Coins is a tarot card from the minor arcana Suit of Coins. A Knight is considered the appropriate card for a male teenager or young adult. Coins are considered the darkest of the suits in terms of choosing based on appearance and represents dark-skinned, dark-haired people. A Knight of Coins would be used to represent a young man who has a dark complexion and features. The card might represent someone who is stubborn or hard-working, serious, and set in their ways.
Kyūyaku Megami Tensei
Megami Tensei II