I just asked about this over on Gamplay Questions; One of my fisherdwarfs got chomped by a sturgeon, and his assigned dog hung out on the site until the (now-named) sturgeon attacked again. The dog won, but suffered mortal injuries in the process. Sadly, instead of getting a coffin like he deserved, he was tossed on the refuse pile.
Dogsashi saw his master be attacked by the foul creature of below.
His master perished, torn from this world and thrown into the next. Dogsashi had failed to save him.
Without an owner, Dogsashi was without honor. He was a despicable piece of trash. An eta. He vowed to fight, he vowed to avenge his master, so that he might gain his honor back.
Dogsashi waited. Day and night until the beast once again revealed itself.
The battle was fierce and the river ran red with blood, Dogsashi appeared victorious! His master avenged. Fate did not smile on Dogsashi this day though, because he suffered a mortal wound.
Dogsashi made it back to the city before collapsing. While his bravery had been proven it was too late. Dogsashi had been a horrible servant.
He did not fight when his masters life was in danger. He only fought when his own honor was.
For this reason the elders throwed his body in the trash. To be ground up and forgotten ... but the fierce battle in the stream would never be forgotten. Neither would the unnamed warrior dog who fought so valiantly and freed the peasants from a demon most foul.