Jeff, I am what is known as his "personal representative." Back in 2021, he and I met with his lawyer and we drew up the documents. I am his medical and financial POA (power of attorney) and am in charge of disposing of all of his assets. Somehow, I never thought it through because he simply didn't have anyone else...no family, relatives or heirs.
Edited to add: yes, I'm managing his remains as well. He wanted his ashes mixed with those of his beloved dog and scattered near a stream. I'm also in charge of making some generous donations to his favorite charities and to his housekeeper.