The Misfit of Demon King Academy (WN)

After a span of 2000 years, the ruthless demon lord has returned through reincarnation! However, his reception at the academy designed to groom potential demon lords is far from stellar – his aptitude is labeled as inept? With the power to vanquish humans, elementals, and gods, Arnos, the demon lord, grew weary of ceaseless wars and strife. Craving a peaceful world, he opted for reincarnation into the future. But upon his return, he found a world accustomed to peace, resulting in his descendants possessing weakened magical abilities. Arnos enrolled in the Maou Academy, established to identify the demon lord's reincarnation, only to be labeled an "inept student" due to his overwhelmingly extraordinary powers, baffling the academy's judgment. Underestimated and shunned by most, he forms an alliance with Misha, a girl who befriends him, striving to ascend the demon race hierarchy and reclaim his former title and status.