Gisagamun Mangnanineun 10 Class

The human world is on the verge of destruction after the attack of the Demon King Erodin. After the fight against the Demon King, the Gold Dragon Exigar is reincarnated as Kain Logdel, a human who is a lout that knows nothing about magic. While trying to escape from his sword-crazed family’s duties to stay at the training camp by hiding his sword skills, Kain is on the verge of being exiled because of the unexpected message from his Family Head... Amidst all of this, the Demon King, with her new appearance, is also looking forward to reuniting with him?!

(Source: KakaoPage, translated)