Oppps, I killed the dog, but of course I should have walked away because of how suspicious it all seems.
When you said miserable I interpreted it as a chronically or acutely ill dog that is suffering. My neighbours actually have a very ill dog that they refuse to put down. Animal euthanasia is what I thought of immediately when reading the suggestions. There was this one time a bird was struck by a vehicle causing it to be barely alive. One or my supervisors put it down. Something like that is what I was thinking.
The part about a sword threw me off though. If somebody is handing me a sword I hope that this is some kind of other world or other era setting. Otherwise that's a bit scary. If it was another era without tricky legal rules and regulations, and I had a very sick dog ...
EDIT: Bad joke: How much EXP does the dog give? Any rare drops?