From slave to Queen

There was a family that was very poor that the selled their 16 year old daughter ,Luna to the King of darkness, Zackyus to be his personal slave. In return the Zackyus would give them 200k. After a while Zackyus started to have feeling for Luna which she did not return back so easily. What's did Zackyus do to Luna ? Will she ever return those feelings? Go find out.