Yours
He remembers the vows he took before he was allowed to serve his Princess. He remembers, with startling clarity that he did so with the most pride and esteem he could muster from his self.
He remembers, how her smile greeted him on the first day of their lessons together, and how they would learn (albeit err on some facts) about Earth and its oddities.
A very different geography for her to learn about; a very amazing person he had the blessing to be in the presence of.
And so, he decided, that forevermore, he would be hers. Only hers.