When I first went through the 20 questions we went through the Giri and Ninjo by the book. I felt they were very straight forward, but also very tame. I read up on Giri and Ninjo and I feel the book does not describe them well enough... By the book's guidance we don't get good drama pieces.
The book describes Giri as if it is your job or profession. Giri is not your job. You don't put Jedi, or Smuggler in this box. Giri is your obligation that your character must fulfill in addition to any other duties. An obligation may be sourced to a character's Lord, Family, or Society. An obligation to one's Lord could be defending his honor, possibly accepting duels to the death over his lords words. You could serve as a political pawn, being married off to secure a new ally. Maybe your family depends on you for income, and without sending currency to them in addition to everything else you do they may become destitute. Society is also a good influence, you could be required to take part in activities you don't believe in like festivals celebrating fortunes you disagree with. You don't like these fortunes, but you smile and play along as if you do - because its your obligation.
Ninjo is described as a desire. Ninjo is less a desire, and more a compulsion. If Giri is when you do something because someone else requires you do it, Ninjo is when you do something because you require you do it, even if it is to your own detriment. Your character may feel compelled to help the sick, and make miss other important functions or stay longer in certain areas where they've found a sick person they can help. They might disagree with the karmic wheel and seek to honor hinin on the same level they would honor another of their status. They may feel that death is unnecessary and seek to subdue opponent's when possible. This is the part where they basically see something wrong in the world that the world doesn't disagree with, but they do. They take action to make it right, even if it brings unwanted attention or consequences back to them.
I feel with proper description of Giri and Ninjo these can be much more functional terms where now... they feel kinda hallow the way the book tells it. Using the guidelines above I re-wrote all of the giri and ninjo with my players and we're more satisfied with the stronger drive these descriptions give the characters. These are also more usable points of drama because each giri and ninjo has its own conflict without even reaching to contrive contention between them.