Rumble!
The secret passage opened before the duo disappeared inside.
"Huh? It stopped?" Gerald paused and looked in Diluc's direction while they were still in the stairway leading to the room.
"I can't sense him," Diluc said.
Gerald's pupils shrunk when he heard this and he quickly tried to sense if Grey was in the room, but his expression worsened. He couldn't find anyone in the room with his spiritual senses.
There was no way Grey could hide his aura from someone like him. This meant only two things, either Grey was dead, or he was not in the room.
But they sensed him while they were rushing here, even after they opened the passage they still felt him in the room. So there's no way he left the room.
That leaves them with only one possibility, Grey was dead.
"Impossible," Gerald muttered before sprinting towards the door.