Maou-sama, Re Re Revenge!

Mada Ooma, a middle school girl, was once a Demon Lord, and one regret from that life still weighs on her: she never confessed her love to Riri, the servant she cherished. She believed that love could never come true—until Riri unexpectedly appears in her present life. As their past and present become intertwined, Mada, a former Demon Lord, finds herself being led on by the person she adores. Their story is a cheerful, innocent romantic comedy.