This is a continuation of
PART A.
There was a cotton handkerchief in Shion's coat pocket. He used it to cover his nose and mouth. It wasn't to shield against the smell; it was to hide his face. This way, the risk of being spotted would lessen. Nezumi also pressed a white handkerchief to his mouth.
They climbed the stairs. The odour gradually grew stronger. Still, the security alarms didn't go off.
A chime sounded, and his feet froze on the spot. A bead of sweat rolled down his temple.
"Commencing odour removal. Commencing air filtering. Operational level 8.5. The air quality of the building will return to normal in approximately two minutes, sixteen seconds."