Room 13
A locked wood door with two golden numbers, labeling this as room 13. The door and surrounding wall look almost brand new, untocuhed by the corruption infecting the rest of the hotel.
Locked: The door is kept locked by its inhabitant Alexis Atherton. Paranoid, he will only open the door if he is convinced that those knocking on his door either have a library access key or knowledge of corruption to trade. Alternatively lockpicking, force or using the staff keys can gain access.
Inside
A clean single room, brightly lit by warm lamps floating overhead with an elegant table at its center piled with papers and books. A comfortable couch sits to one side of the room and a bed on the other, intricate rugs line the floor. The room is untouched by the twisting effects of corruption appearing brighter, warmer - almost like new.
Papers and books: Succeeding on an Intelligence or Medicine check reveals that the papers and books are notes and research of a slug like creature which ingest and remove corruption from objects or creatures. With tests noted as succesfully removing rot from the room, later notes suggests attempts at removal of corruption from a living test subject. The notes become illegible soon after.
Untouched: A strange thin slime coats parts of the walls and furnature, everything looks almost like new compared to the degradation of the rest of the hotel.
The Alchemist
The Alchemist Alexis Atherton is a spindly gaunt man. Hidden in his coat a jar full of Rotbane slugs. He has been studying them and using the slugs to clean his food and room of corruption. Succumbing to corruption himself he has used them on himself though has slowly lost his grip on reality as they have fed on him. He is happy to make a trade for one of his many Rotbane slugs for an access pass to the hotels library.
Item: Rotbane Slug
Removes corruption or poison from an object or creature. If done so with a creature make a DC18 Constitution saving throw, on a failed save the creature permanently reduces their Intelligence by one.