Whew, that was tough but fun! Took me 3 tries on Normal mode.
I don't know if I have a lot of new feedback, other than echoing what others said! The atmosphere/graphics/style was all really great! The ocean and boat setting felt very unique, and it was all well-realized. The story at the end was cute and funny, I enjoyed it. Overall I think this was really great! I suppose I have a few nitpicks so it's not all gushing...
First, I liked the story, but i wish there was more at the start. I had no idea why I was chasing and fighting this ghost girl. I imagine this is a time-constraint issue mainly. Second, a little more feedback when hitting the ghost girl might be nice... a louder sound, more visual feedback. As it stands, it's OK, but kind of hard to tell if I'm hitting without glancing at the health bar, which is tough while dodging and fighting. The last nitpick that came to mind was that the mouse sensitivity felt a little low. I really had to swing my arm to get the camera to move around, especially when a ghost boat was approaching from behind.
Nitpicks aside, this is definitely a top contender of MGGJ6! Great work.