For a direct answer to your question.....
If a TM comes after you own the domain and they come after you, they would be reverse hijacking. They may harrass you to no end, but you do not have to sell. If that ever happens, take them to court.
But remember, a TM does not have to be registered to be a TM. If they had been using the TM before you registered it and they register thier TM with USPTO after you registereed the domain, then that is a different story. Fisrt usage is a determining factor of a TM, not when if it filed with the government.
Keep in mind, using your name or product for commercial use gives you a TM, registering your TM gives you the government backing that the TM is yours.
I think he was asking if the TM occurred after he had the domain.