Soon.
It was what he told himself whenever he found his pencil hovering over her name on the ledger.
Soon she would be debt-free - and free of them. Soon she would be gone from their lives for good. Soon Tamaki would wake up and realize what was right before his eyes. Soon Haruhi would accept that she was a girl and that she had feelings for Tamaki as well.
Soon he would be forced to watch as perhaps the only friend he had in the world romanced perhaps the only interesting girl in it.
Soon, Kyoya would be forced to act. A broken plate here; a chipped cup there - costume rentals, cakes - it all added up - and kept that day from arriving. It was imperative that it never come, that he prevent that which he knew must be.
Soon she would be free, and he would lose something he didn't even know he had: his heart.