Chang-Foo Soon is a stress eater.
His job can't be that easy and his wife is unknowingly not helping his situation. People in the 19th century (or that long ago at least) wouldn't really know anything about that condition or wouldn't really pay any attention to it to tell him to knock it off lest he drops from a heart attack. Lik-Lik is gay.
He speaks with a very stereotypically "gay" voice, dresses in a very flamboyant fashion, plus he has a huge jawline compared to the other cats. The Foolish Magistrate is a Time Lord
Would explain why he gave his daughters a modern-looking bike in a episode of a series that takes place in Qing Dynasty China. The palace is his TARDIS.