Sendai Yuusha wa Inkyou Shitai Novel

A legendary hero summoned three years ago defeated the Demon King in Leezalion, saving Reinbulk from destruction. Now the Kingdom of Luxeria performs a desperate summoning ritual to bring forth five warriors to confront the Demon King and his demon army once more. Among those chosen is Yashiro Yuu—a summoned hero with no magical affinity and no recognition from the kingdom that refuses to send him home. Unknown to all, Yuu is the legendary Hero who defeated the Demon King three years prior. His awakening to the situation brings confusion: the Demon King remains sealed, never escaping his binding. If the seal had truly been broken, Yuu would have been summoned automatically, not through this ritual. Since he has already saved Reinbulk once and the seal holds firm, Yuu makes an unexpected choice: he will leave the new heroes to face the supposed threat while he pursues freedom from the hero's burden. Abandoning his destiny, he becomes an adventurer.