"Even if it is a great hardship? If it will take many days,  put you at risk of injury or worse? For there is an artifact that could defeat him, though retrieving it will be a rather arduous task."

"I'm not going to give up. She's my sister."

"Good! A heroic spirit! Off to the East we sail! Except... Though it pains me to admit, while I am a boat that can speak, I possess no sail. We cannot exactly make good speed without one. I'm afraid I have to ask you to search this island for a merchant who will sell you a sail."

"Okay."

Time to go merchant hunting. She still has all her things, right?

"Good luck. If you are short on rupees when you find one, I would suggest finding some tall grass and cutting it. People drop all sorts of things in grass."

"Right. Done that myself once or twice."

What's the island outside the cave look like?

It's a cheerful little place. Gentle slopes, lots of somewhat old-looking houses and shops, people wandering about amiably. The first part of the island has a few little kids, an old man, and a couple of strong-looking types wandering about. There's also a postbox, and a lone shop separate from the rest of the town off to the left.

Neat. She'll check out the shops in the main part of town first.

The first shop she tries appears to be an apothecary of some sort... Dimly lit, weird smells, racks of herbs and chemistry-looking equipment in the back.

Kinda cool, but not really what she's looking for. She needs a sail for the magic talking boat so she can find the thing and save her sister. She should probably get more details about the thing. But first, a sail!

Wait come back won't you listen bring him chu-chu jelly from dead chu-chu monsters and he can make you healing potions!

...What is a chu-chu monster?

This thing that he has a picture of. They're relatively well-known pests, pretty common, just apparently not on Outset Island.

If she runs across any, she'll keep his offer in mind.

The next shop she sees while walking along is an auction house that announces itself closed until nightfall. After that is an outdoor stall run by some sort of eskimo. Someone wearing even more unseasonably warm clothes than her, anyway. Except, he doesn't actually have anything displayed on the counter and looks pretty depressed. After that is a combination coffee shop and bookstore.

She stops by the sad eskimo guy.

"Are you okay?"

"Oh. Not particularly. My story is a strange one, and a bit long, though..."

Well now that she's gone and actually talked to the guy she's got to follow through.

"Tell me."

"I came from a land far, far to the north, where it's much colder. Have you heard of snow? We have storms of frozen water falling from the sky. I came because of this town, Windfall. It was said to be the greatest gathering of merchants in the world. But as we grew near, the winds became vicious and evil creatures plied the seas and skies. My ship was torn apart and I washed up here... But I was not alone, and this is the terrible part, my only true friend was thrown in jail by the locals simply because he looks somewhat suspicious and behaves strangely! And I just know he's locked up somewhere. Needless to say, I'm worried about him."

"I'm more local than you, I could ask and see if I can find him?"

"If you could find him and free him I would be very, very grateful."

"I'll see what I can do."

Moving on, except now she's for a jail or town hall in addition to a sail shop.

Camera shop. Schoolhouse. Bakery. Some sort of monument out on a jutting spar of rock that is over where her talking boat's cave is..

The biggest, most important-looking building in this place is that auction place that apparently doubles as a rich guy's house.

Okay... How about that shop that's separate from the rest of the town?

It's a bomb shop! With prices that are entirely out of her range. Ridiculously high, really. And the proprietor is rude and haughty. "Think a kid like you can afford anything in here, eh?"