Am I the only one who thinks that the best possible outcome is a polygamy ending with the ghost? That possession thing could circumvent the whole "can't handle the beauty/amazingness of the princess" that stalls the princess's relationship with the hero.
Ghost-chan could just possess the princess when she is asleep.
More typos
page 5 third panel: "I am you're knight " should be your.
page 16 second panel: It mus be a fate[...] should be must.