The emaciated boy's aura was glaring in Yun Jhin's perception, which meant that he had a unique constitution or bloodline of some sort!
This young boy's appearance also made him think about his 'family' that he had on the vermillion bird planet, he still felt the connection between his son and daughter that he had created, they were pretty much 'clones' of his with a unique will that was subservient to his, while they didn't have any of his experience nor memories they would mostly act like him.
Quite a bit of time passed so they must be in their teenage years by human standards, while they were conceived when he had the weaker bloodline of a dragon caterpillar they were talents that could reach the God Realm if groomed properly as most of the time the offspring would end up more talented than the parent.
Of course, this was something in reverse for Yun Jhin's bloodline but he could feel when he analyzed their bloodline was equal in purity to his, at the time.