He donated an astonishing 128,000 zorkmids to friendly priests, and never attacked a peaceful creature.  (Strange how so many chose not to be peaceful!)
As for his other conduct...
After his cat Kit Fisto picked an ill-advised fight with a watch captain in Minetown, he only felt slightly guilty about occasionally eating food that would otherwise be wasted.  His pet killer bee named Baybee didn't survive the dungeon either.  And one is obligated to make use of a divinely-gifted sword, right?  There was dancing with demons, and nurses in a graveyard.  Experimenting with polymorph control turned him into a woman temporarily, which may have caused him to lose interest in dancing.  Mind flayers are annoying far beyond their ability to kill you.  One inflicted him with amnesia, so he had to genocide all similar-looking humanoids in reprisal.  And then once one has committed a genocide, why not a couple more?  Goodbye, liches and cockatrices.  After looting Ludios without finding so much as a crummy sack, he resorted to poly-piling for a bag.  Then he polymorphed into a black dragon to disintegrate Master Kaen.  He eventually started sporting dragon scale mail and a shield even though monks aren't supposed to wear body armor.  He plundered the grave goods of "dareman" (killed by a mumak while reading a book) to get Magicbane and other goodies.  The Astral Plane went very smoothly after eighty thousand turns of preparation.  He chose the correct curtain behind Famine to ascend with 3,994,254 points and armor class negative 49.