The "bittersweet, mysterious story" revolves around Chocolat Aikawa, a chocolatière who runs a shop called Chocolat Noir. She can grant wishes to the troubled people who visit her shop — if they give her something precious in exchange.

In the Chocolat no Mahou (The Magic of Chocolate) series:

V.1 - Chocolat no Mahou
V.2 - Bittersweet
V.3 - Creamy Sugar
V.4 - Dark Spice
V.5 - Evil Essence
V.6 - Fruity Flavor
V.7 - Guilty Crunch
V.8 - Honey Blood
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? Doraje Koibitotachi no Kiseki