Zein might not have mana anymore, but he was naturally agile even before his awakening--perhaps because he had to keep running away from the bullies in the red-zone--so before everyone realized it, he had already disappeared inside the mansion.
"H-huh?"
Bassena, who finally woke up from his stupor, immediately chased the guide inside. The house staff readily gestured toward the nearest bathroom before Bassena even asked, and thanks to that, he arrived swiftly without needing to search for a single man in this castle.
So he managed to see Zein throwing up into the toilet bowl.
For a few seconds, Bassena's vision darkened. Memory brought him to the night Zein poured the content of his guts and his tears; the coldness, the pain, the agony of that retching sound invaded his mind and made him stiffen at the door.
When he came to, Zein had already flushed the toilet.