The Stormborn and the Stormbringer (джен)

The dragon has three heads.
 
Daenerys had been taught about dragons, about her family history and the great beasts they rode. About their thick hides and near impenetrable scales. About their horned heads and fanged maws that can spit fire at a moments notice. About their leathery wings which sounded like the roar of thunder with each beat.
She had never been taught about them having multiple heads. The three headed crimson dragon of her House's flag was to represent Aegon and his sister-wives, of the three dragons they used to bend the Seven Kingdoms to their knees. It was figurative.
But this one she cradled to her breast had three heads at the end of its sinuous serpentine necks. The crown of each head was dotted with small, barely-there horns with more along the length of the spine. There were also two tails, the barbed tips curling around her forearm like a babe clinging to its mother's finger. Its scales shone like gold, glittering through the ash coating its body.
 
The dragon has three heads.