Whether the reason for fondness be the way they look, their backstory, or their ability, everyone has an NPC they have grown fond of over their many months of playing WoW.
My personal favorite is Garrosh Hellscream
Because he's the epitome of power, and badassness. He's evil and an ideal leader of the "Horde", not to mention he's merciless and bloodthirsty....he also aced Cairne Bloodhoof, an ambivalent event.
He knows what his people are capable of, and the reputation they should uphold. Since he assumed the role of Warchief, he has given everyone a vision of what it truly means to be apart of the horde.
During The Shattering, he and Cairne are en route back to Ogrimmar for a celebration held for Garrosh, but on the way he "...waylays an Alliance carrier wrecked at sea. He disposes of most of its crew, reasoning that it is in Horde waters, though a distressed Cairne urges him to relent. Garrosh then gives the survivors supplies and rations, informing them that they had witnessed both the Horde's might and the Horde's mercy."
So who's yours?