After a year of being taught by his Master, Claude is no longer ignorant about the common knowledge in the universe.
A heaven's blessed and the realm's chosen are not exactly a secret in the universe. Of course, detecting such people is only possible using special means or when one's realm is powerful enough.
For example, a 6th rank Sage Mage can easily detect the presence of fortune aura and know when a living being was a heaven's blessed or a realm's chosen.
With the knowledge he possessed, Claude found it incredulous that he actually obtained the fortune aura of another realm.
Despite the Earth Realm's destruction, Claude still has the imprint of his birth realm. Even his Master cannot remove it. This invisible imprint is proof of his origin, and with this imprint, it should be impossible for him to be a heaven's blessed or a realm's chosen of a different realm.
