D-kyuu Boukensha no Ore, Nazeka Yuusha Party ni Kanyuu sareta Ageku, Oujo ni Tsukimatowareteru

If you become a hero and defeat the Demon King, a life of idleness awaits you...! This is what the young man Jirei believed, and he works hard day and night to achieve his goal. However, when he finds out that the heroes who defeated the Demon King were the ones who were doing all the hard work, he ran away. But the girls that Jirei had been saving on his journeys before he knew it came pouring in one after another to win his heart and body...?

(Source: Overlap, translated)