My favorite lore character is Sinestra/Sintharia, Deathwing's prime consort. Her tale, though she was evil, was also very depressing. After Deathwing went insane they did end up mating, but the heat from the molten magma on his body was incredible, enough that it killed all his other mates, she lived, but she was charred horribly, loosing an eye, and making her look kinda like a Forsaken. She became abosloutly evil-insane, created a new dragonflight, the Twilight Dragonflight, dragons of amethyst.
Eventually, her "son" Dargonax (which means Devourer), after being fatally destabilized by the dying Zzeraku, killed her. A sad end to her tale.
And Deathwing, too, wasn't always evil.
Raydex-level 80 Nelf BM/MM hunter, Dawnbringer
Cloudwing-Spider (stupid name, no?)
Drassil-level 28 Nelf feral druid, Dawnbringer