When a god was in the realm of Cretea, it was almost impossible for them to get exhausted or tired like that of humans. They were powerful beings.
However, Raphael spent a better part of the last year simply being in the human realm, and even as the Seventh Prince, his own strength could drain.
He and many of the other gods went to great lengths to ensure that King Draco's letters weren't delivered into the world. When they failed to do that, Raphael chose to redirect his attention and assailed some human princes to discourage and dishearten them from going on a journey.
Raphael did it all while making sure that his fellow companions, his friends didn't butt heads or accidentally gave away their positions.
If his father, the King of Cretea, figured out what exactly the purpose of Raphael being in the human realm was for—there was no doubt going to be issues.