Maou-sama, Re Re Revenge!

The junior-high girl Mada Ooma recalls a past life as the Demon Lord. She (he) has but one lingering regret about her previous life: that she wasn’t able to confess her love to Lili, her attendant. A love that would never come true... or so she thought, until Lili somehow appeared in front of her eyes in her new life...!? A bright and pure romantic comedy weaving together the past and present lives of a former Demon Lord, who’s now being taken for a ride by the one she loves!

(Source: Shogakukan, translated)