Angelique Duet is a spin-off of the first Angelique. It offers players the ability to play as Rosalie, the rival of the first game.

The gameplay and flow remains much the same to the first game if the player picks Angelique, but has altered romance events for Rosalie to distinguish it from the base game. It also includes features and events that were added in Angelique Special 2, such as the gift giving and written date invitations. On top of that there are now Friendship events between Angelique and Rosalie. There is also a change in character portraits and backgrounds as they received a graphical update.

The DS port includes a communication mode taking advantage of the wireless connection capabilities the Nintendo DS. This allows players to message each other and trade items through an in-game messaging system and room visits.