Hello, I just started using a controller today (Xbox) First of all Do you have a wired controller? its alot easier if you do. All you need to do is plug that Controller into your computer/laptop once you've done that its best to test if its working, I'll give you some steps:
1.On your computer, click Start, type Run, type joy.cpl, and then press ENTER.
2.Select whatever controller your using, and then click Properties.
3.Test your controller by pressing a button, pulling a trigger or moving a stick on the controller.

All you need to do next is start Onigiri up and when your selecting your character it will ask you if you want to use your game pad, just click yes and you should be playing Onigiri with a controller

I'll will also tell you this, you cannot talk to people or accept things with the controller so you will have to use a mouse for that.

Hope this helped

Aim to select npc, press B, and B again to flip through dialog