Ian would have to be stupid not to notice the elf and demon tailing him and Ava last night. The demon reeked of dark magic and the elf was not good at hiding himself at all. It was a miracle she hadn't spotted him.
He deduced they must be the descendants of his old friends immediately. Why else would such an unlikely duo be spying on Ava in the human world?
So many years had passed without the other guards showing up. How unreliable were the elves and demons? Ian had known immediately when Azariel's reincarnation was born.
Granted, he was actively searching for her throughout every dimension he could possibly travel to but still. Their reaction times were pitiful. Perhaps it was because their motivations couldn't compare to his.