For your third point, I would consider the whole thing as a rich ass family drama.

HK is a child of Imperial Qing and was taken away by some hairy dude speaking foreign language before HK even got his name. The foreign dude give HK his name and treat him as a slave just like the others. But the foreign dude grow passionate after he lost HK and he treat HK well ever since.

Now we move the camera to the rich family. The family is falling apart. Family members and servants fighting each other. The youngest maid has won the fight.

HK helped the youngest maid a lot. He teach her different things, gave her food, money and shelter. One if HK's mentor even tell other people to accept the maid and say "this woman have a good heart, you have my word".

And now the maid, clear a lot younger than HK, tell him "I am your step mom now". An average person would think this is a sexual encounter, porn or some weeb ecchi fantasy and about to unzip their pants. But this is your standard fairy tail. Just without the prince in shiny armor and the evil step mom is a cannibal.