[he echoes that like he needs to say the words out loud to remember what they mean. He says them into her shoulder, since she's hugging him and he's holding her]
Oh... oh.
[revelation dawns inside his Mayorly little head]
But that does explain his behavior! The absurd secrecy, and his embarrassment...
[he remembers something, and takes a little breath]
Oh, PM—I should have suspected right from the beginning! From his arrival—how foolish I've been! In the desert, he—I ought to say the both of us—behaved in a manner precisely consistent with such feelings. It has been so long; it had slipped from my memory. [a bit apologetically:] I do not like thinking about the desert.