I feel like he probably kept tabs with his little minions since the vow would force him to stay out of sight/crossing paths. And when he dies, since the soul leaves he’d be able to retrieve his corpse to bury. As some sick way of mourning/regretting what he did.
I’m wondering why he’s allowed to now. Since if he knew it would kill him young, why still lure ha on to him?
Plus we’ve seen the foxes curse still lingers, so that could be a different reason for his reincarnations dying.

The past line makes is really hard to appreciate ML in the present time. He treats him badly and doesn’t even grant his wish…
I do love the MC standing for himself and asking the dragon lord to disappear from his sigh in any reincarnation. It makes me wondering if something is gonna happen to the ML in the present since he isn’t supposed to see him. Some kind of curse or anything.
I do hope by the end of the story we can see ML making amends to past MC.