Follow the path through the woods. There are a number of "battles" in here before you finally find the horse with red wings. They're not "Boss" battles, but I'm pretty sure you have to complete them in order to move the story forward. And besides, they're blocking the way to valuable treasure.

1st "Not Boss" Battle

Fairy, Autumnwood x2

105EXP/66SP/1610G

These are honestly just regular enemies. Just use whatever skills you want, and then get the treasure and keep going.

2nd "Not Boss" Battle

Fairy, Paralysis Mothfly x2

Again, just typical random encounter enemies. Just kill them and move on to the next screen. (Sadly, there's no treasure after this battle.)

On the next screen, your first Boss battle is with a human instead of a monster. As you approach the human, she mistakes you for the bunch that's kidnapped her brother.

Boss Battle

Jane

This battle takes a long time, but as long as you watch everyone's health you should be okay.

I used Let's Trade! on Jane, and stole an Attribute Ring B, but aside from that I used all the strongest attack skills I had. (Plus, I used Attack Down and Guard Down, and that seemed to help quite a bit.)

After the battle, Jane reveals that she was the robed woman you bumped into in Hwael Village. As she's leaving, she drops an old photograph. Izayoi and the others try to figure out who Jane might really be, but then they remember they're here to track down a monster. When the dialogue ends, keep heading west to your next battle.

3rd "Not Boss" Battle

Man-Eater, Unicorn x2

Seriously, just use whatever on these guys.

After this battle, you hear the howl of a monster from deeper within the forest.

Keep going west, and when you reach the next screen, step on the gate to be transported to a deeper part of the Grove. The monster you're looking for is on the second screen in this part of the grove.

Boss Battle

Red-Winged Centaur

Okay, I started this battle by using Guard Down and Attack Down, then I just used everybody's strongest skills until I ran out of BP. After that, I used a combination of skills, magic and healing items until the Red-Winged Centaur was dead.

After this battle, just use an Exit Feather to get back to the start of the dungeon, then go to Gemini Town and talk to Jolie Curie.

Back at Gemini Town

Jolie tells you she can have a ship ready in the morning, so go to the Inn. At the Inn, Izayoi makes contact with Minerva, and you learn that Jane Glory is the great-granddaughter of Keith Glory.

(In Asdivine Dios, Keith was near death at the end of the game. Izayoi embued Keith with a small portion of his own divine powers in order to keep him alive. Now, his great-granddaughter has inherited that divine power, and that allows her to cross between worlds.)

After the dialogue, you have free time.

Free Time

Ratona: located on the harbor; answer "Let's work together!"
Litany: located in the northwest corner of town; answer "If that happens, I'll save you."
Noelle: located in the Item Shop; answer "Like this?"

In the morning, go back to the guild and Jolie gives you a boat. Now that you have a boat, your next destination is Polaris Shrine.

Treasure

• T1 - Buster Ticket x5
• T2 - Metal Arkstone
• T3 - Shiggy-Diggy-Do Rod
•       (Paralysis 12 Fatigue 26 Confusion 30)
• T4 - Guild Saber +6
•      (SPD 12 Countdown 12 Crit 22)
• T5 - Tray Pearl
• T6 - Bronze Rod +32
•       (Steal 12 Gnome 18 MP Recovery 20)
• T7 - HP Seed x6
• T8 - Rasetsu +18
•       (SP 20 Crit 16 Steal 15)
• T9 - Follow Arkstone
• T10 - Treasure Searcher x5
• T11 - Filthy Pearls
• T12 - Stunned Doll +4
•         (EXP 10 Gold 12)