So, I have taken to playing this demo, and I don't exactly have much good to say on it.

The Bad:
-Right off the bat, the English (translation?) is an eyesore. In the first two or three bits of texts in the prologue I spotted several errors that near-immediately took me out of the feeling of wanting to hunt down the treasure and be part of the adventure. The dialogue doesn't suit much better, either. I would highly recommend finding someone who speaks fluent, and proper, English and have them do a revision on what I assume to be translation. Even if it isn't, a little revision will go a long way.

-The plot is... nonexistent? Doesn't make much sense? The prime example I can think of off the top of my head is when you can actually start moving around as the character. The prologue states that the father, Hugh, convinced you (the son) to go on this adventure, yet the dialogue has him questioning the son as whether or not he's sure he "plan(s) on leaving today". Like, what? That's a contradiction. What even is the reason behind Hugh convincing his son to seek the treasure? Why does the son not question it?

Additionally, the first thing you're greeted with at the Sunset Eagle Island is the mayor, who asks you (a total stranger) to retrieve an emblem from a dark-clothed woman in a mine... Who does that? You say nothing to the guy, and he immediately asks the first person that comes to port to do a rather dangerous mission? Also, contradictory to the title, you don't spend very long at sea. Lol. All I've gotten from the plot, as a whole, is that I'm off to find some treasure, my girlfriend came alone because "Why not?" (quoting to the main character), and we're helping a total stranger get back a pendant that has unknown purpose and value as a mere favor.

-The lack of abilities/spells is annoying, frankly. There isn't much more to say on that. If you aren't intent on having abilities/spells, however, that's fine... just take that out of the menu, like you should with the 'save' option.

-Atmospherically, there is no music anywhere aside from whenever you enter battle (to which I do give credit: The music selection is well-done). I also noted that the noise of the ocean outside could be heard as clearly as if you were standing right next to it. That isn't good and needs changed. It's also, I think, out of place to have the villain spout a single line of dialogue, albeit before battle, while literally everybody else remains silent. I'd recommend making up your mind on whether or not you're going to have everyone have a voice or not. It's really out of place to have just a few people with a voice.

The Good:
-Like I mentioned already, the music choice is nice for where music exists (only in battle).

-The map of the mine you go into is pretty well-made. I like it a lot and felt as though it actually was a mine of sorts. Though, it looks abandoned; I'd have assumed the town would be using it for something? Keep it in some good shape? I dunno.

-Speaking of maps: The World Map is pretty nicely-made. I like how it's a grid-esque map and has "Random Event" spaces (the one that exists doesn't work when you first go over it, by the way). It reminds me a lot of Mario Party.

Verdict:
As it stands right now, I wouldn't play this demo again, nor have much anicipation for the full release. I give this a 2/5 rating.