In addition to the main clans of the Kuroa and Akadama, there are a few other villagers floating around town. They help keep the storyline interesting, and add a Yojimbo-like atmosphere to the whole thing.

Suzu
Pretty much central to every storyline, Suzu is a poor little waif that it seems just about everybody wants to marry. She's sweet and kind, was orphaned at an early age. Dona is writing love poetry to her. Tsubohachi is trying to kidnap her at the beginning and joins you against the govt near the end when he realizes she is in danger.

Dona Dona
This African has joined the samurai and intends to follow the path for his entire lifetime. He's pretty useless as a fighter but loves Suzu dearly and will do his best to help her, from taking on Tsubohachi under the bridge when she's kidnapped to going to the Kuroa mansion and stealing cash for her.

Grandfather
This guy is pretty much immortal. You can't hurt him at all. Which is lucky, because he's beaten up by the Akadama clan in the middle of the day for no real reason.

Donjin - the Blacksmith
Donjin is really important for upgrading your swords - it's amazing how much difference a good sword makes in a fight. Also, he adds the various Yojimbo-like comments about "it's always the poor that suffer" and so on. By Day 2 he wants you to help him put a stop to everything.

Policeman
He's a slime that the government instruct at the bridge to keep an eye on the town. You find him soon afterwards laughing while an Akadama rat beats up on the grandfather. He's having an affair with Murasaki, the wife of the Kuroa leader. But he usually dies in the end.

Toyoko
You'll find him lurking around the shrine in the evening, and in other places. He wears a purple robe, and he'll tell you (after you defeat him in battle) that there's a secret back entrance to the Kuroa place. This is really only handy during the rescue-Dona mission, because it lets you get in to where Dona is without alerting the guards. If you don't talk to Toyoko, the door won't be open for you.

Way of the Samurai Walkthrough