Mahjong Eiyuu x Maou

Felser has successfully conquered the whole continent and reigns from Feelese Castle with his demonic minions and lieutenants. One day, they discover a cursed mahjong set that is said to allow one to impregnate a defeated female player with powerful demonic beasts... But the Demon King soon realizes his new offsprings are hopelessly wild, and he can no longer father normal children due to the curse ! With his main source of reinforcements shut off and his heroic nemesises on the loose, Felser's position appears unstable...