TSUIHOU YUUSHA NO YUUGA NA SLOW LIFE: JIYUU NI NATTARA ORE DAKE NO SAIAI TENSHI MOTE NI HAITTA!

After suddenly being fired despite serving as a hero for 30 years, Alec was left with nowhere to turn. Orphaned from a young age, he had no parents to rely on, and having been a hero since childhood, he lacked basic common sense. With nowhere else to go, Alec ends up at an unexpected place—a slave market!? There, he encounters the beautiful and kind-hearted Lilicia... This is the story of an unwittingly strongest protagonist and an angelic heroine weaving an excessively naughty second life together. (Source: Square-Enix, translated) — Description from AniList community (anilist.co).