Honourable can be earned by helping some NPC characters along the way.
You need to offer an herb for the Old Key at the very beginning of the game when you can first earn the "Helping Hand" achievement (at 8:45 in the video below).
The second, and final one for the achievement (at 44:30 in the video below). You sheath your sword and then give an herb to a hurt elder in exchange for the Woad Kipu.
It seems that you can save another NPC just after the 2nd (46:00 in the video below) from a fight with an enemy but that doesn't seem to count, the achievement should pop after the first two as stated above. (Several gamers have reported that they needed to save this 3rd NPC for the achievement to pop)
For all achievements in the game, you can follow this awesome guide on YouTube:
All credit to Trophy Tom. Please like or subscribe to support him. Please note how he has conveniently labeled sections of his video based on which achievement is next or what item you are tracking down, this can be seen if you watch his video on YouTube on the video progress bar instead of the imbedded video here on True Achievements. It is a very well done 100% guide.
You will also nab "Helping Hand" while going after this achievement.
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