@Ikki_ that's how manhwa like these go. The major side characters and their connection to mc are usually what is concentrated on first and mc is presented as a mysterious being whose existence cannot be explained. Later, they begin to unravel the mc 's backstory slowly, it usually ends with them being an eldritch god who gained interest in humans and decided to walk amongst them. Similar manhwa are "I'm not the demon god's lackey"(he is revealed to be an eldritch god at the end but clues are provided throughout the story), "raising the villains the right way"(mc seems to be connected to an eldritch god).