Bayonne is the unlikely main hero (yeah, yeah) from the southern continent of Drozd. He was raised by his father only, who was an artist but also in search of something called "the Crest." After Bayonne got out of college he found himself aimless, indecisive and flat broke. Some time during this period his father died and told him to continue looking for the Crest in Baroth. Bayonne traveled to Baroth, where his journey began. Bayonne is timid; young and naive, but not stupid; obviously his transformation from weakling to hero will be a big part of the storyline (yeah, yeah).
Arzachel is one of King Harry of Baroth's consuls. He practically grew up in the castle serving the royal family and is flat-out rude, but still playful and anything but a novice. He is the constant source of intel and also torment to Bayonne when they meet in Baroth and far into the game. He's also got some kind of deep dark secret that even he is possibly not even fully aware of.
The Callows family occupies the portion of a short-story in this game. They are a rich family going back many generations that established Cape Lucid, to the east of Baroth, as a trade bloc and port. They're likely to show up later in the game too.
Nepenteth is the penultimate evil dude/guy. His true motives are unclear, but it's obvious that he's out to hinder Bayonne's path and obtain "the Crest" for himself.
Yuri is also one of King Harry's consuls and very close friend to Arzachel. Why she then turns traitor and joins Nepenteth in hindering Bayonne and Arzachel is as of yet, uncertain.
Himmel is a fisherman that lives with his family in Reubezahl, southwest of Baroth. When Reubezahl becomes "cursed," he joins the party to travel through the mountains to find his family and help return Reubezahl to its former state. When we first meet Himmel he has a very serious personality, which clashes largely with Arzachel's. He mellows out a lot later on though and Arzachel and he actually become somewhat chummy.
Cosmi is the fourth and final regular party character. She went to college with Bayonne and eventually ended up teaching in Bayonne's hometown afterwards; whether this was coincidence or not is unclear. Bayonne and her are great friends that maybe care about each other far more than either will let the other know.