Aside from the green light from Luis' Revitalize Skills, silence blanketed the two individuals. Well, that is if they exclude the thunderous explosion and the shriek of the stone golem in the background.
Luis was torn between two heavy choices but before he could come up with a decision. Xagrien has already said it with all certainty. "You did, right? And that is the repercussion of the Oath of the Soul. That oath that I asked you to take restrains you from causing any harm to my comrades."
Luis' blade must have carelessly grazed Nereen's sphere and that counts as a grave harm on Nereen, thus triggering the Oath of Life.
"You didn't look tired at all earlier and before that, the Golem didn't hit you that time. But you clenched your chest as if your heart was being squeezed and your complexion suddenly turned deathly pale."
Even though Luis knew that Xagrien would point it out, he was still surprised, especially when he saw how certain the male is.