The secret that Ignis hides.

Seeing Ignis pass by him and heading towards the sarcophagus, Isaac frowns, seeing his forehead oozing with drops of sweat.

'For Ignis to be so careful, the content of this sarcophagus must be sickening. Earlier, I briefly saw an expression that Ignis had never shown before, fear. It was fear that I read on his face!

-Why? I mean, why didn't I feel that same dread? I know I'm reckless, but not to the point of being crazy about something that can even frighten the direct subordinate of a former supreme. Apart from the pressure that gave me sickness and a headache, I did not feel anything particular that could be characterized as fear at the aura.' Isaac looks at Ignis's back, patiently waiting for him to secure the area.

Even if he struggled to keep his curiosity under control by dint of waiting, he knew that he was weak, so weak that he would only be a dead weight for Ignis.