Ramsay Bolton
Roose's baseborn son, a grinning, sadistic young hunter with a pack of hounds and a taste for cruelty that even his cold father finds difficult to leash.
A soul born at The Dreadfort, sworn to House Bolton.
The fuller tale
Season Three
Bastard of Roose Bolton, and the reason Theon Greyjoy never makes it home after Winterfell burns — his men catch Theon fleeing north, and Ramsay keeps him at the Dreadfort as an ongoing project, dismantling him piece by piece with a knife and a great deal of patience, offering just enough mercy between cruelties to make Theon grateful for its absence. Nobody at Winterfell or beyond knows what's become of Theon, or that the pleasant, soft-spoken man doing it to him is baseborn, unacknowledged, and determined not to stay either much longer.
Season Four
Sent to finish taking Moat Cailin from its ironborn garrison, and does it without a real battle — parades what's left of Theon, thoroughly broken and answering only to Reek, to talk the garrison into surrendering, then puts them to the sword the moment they lay down their weapons anyway. It earns him what he actually wants: a royal decree legitimizing him as Ramsay Bolton, trueborn in name if nothing else, with his father's house and eventually his father's seat somewhere in view.
Season Five
Marries Sansa Stark on his father's orders, to bind Stark lands to the Bolton name, and the wedding night is as brutal as anything he's done to Theon, with Theon forced to watch. The abuse continues for weeks after, and when Sansa manages to get word north for help and then tries to flee with Theon, the season leaves them jumping from Winterfell's walls into the dark with dogs on their trail. In between, when Stannis Baratheon marches on Winterfell, Ramsay slips out with a small raiding party and burns his siege camp's supplies and horses, gutting Stannis's army before it ever reaches the castle.
Season Six
Hunts Sansa and Theon's trail with hounds, and when his father finally has a trueborn son by his new wife, Ramsay resolves the problem the direct way, with a knife for Roose and the hounds again for the wife and infant, and stands unchallenged as Lord of the Dreadfort and Winterfell both. Rides out to meet Jon Snow's scratch army at the Battle of the Bastards and opens the engagement by putting an arrow through Rickon Stark, calm and unhurried, mid-field. Loses anyway to the Vale's cavalry and Jon's fury, is beaten bloody in his own dooryard, and Sansa gets the last word — she leaves him for his own hounds, kept hungry for the occasion, to finish in their kennel.
How it ends for them
On the screen. Killed at Winterfell (S6·E9)
He lost the Battle of the Bastards, his house, and his hounds' loyalty in a single afternoon. Sansa Stark watched from outside the kennel as the starved beasts he'd raised remembered they were hungry.
The show settles Ramsay's account in his own kennels. Beaten half-conscious by Jon Snow in Winterfell's yard — Jon stopping only because beating him to death would have been a mercy Sansa outranked — he wakes tied to a chair among the cages, and Sansa explains the arrangement: his words are going to disappear, his house is going to disappear, and his hounds have not been fed in seven days. Ramsay's last confidence — my hounds will never harm me — survives approximately one sniff. Sansa walks away down the corridor to the sound of his loyal beasts remembering they are hungry, and permits herself the smallest smile of the entire series. In the books Ramsay is alive, un-mauled and holding Winterfell; whatever the remaining volumes intend for him, the show's kennel door is an invention readers can only hope the author finds equally fitting.
Their chapters, book by book
A Dance with Dragons 1 chapter that name them
Where the page and the screen part
The books' Ramsay is less pretty and more feral — fleshy, dry-skinned, dressed in dandy's velvets he wears badly, described by his own father as never truly bathing the blood off — where the show cast a boyish charmer and let the grin do the work. His bride differs materially: not Sansa but Jeyne Poole, the steward's daughter passed off as Arya Stark, a fraud the whole northern court is forced to swallow in silence. And he is alive in the published books, holding Winterfell beside his father as Stannis closes in — the author's infamous Pink Letter, taunting Jon Snow with claims about the battle's outcome, is either Ramsay's hand or someone impersonating him, an authorship puzzle readers have argued for decades. The show also trimmed his gang of Bastard's Boys and invented Myranda, the kennelmaster's daughter, to give his sadism a co-conspirator with dialogue. Both tellings agree on the essentials; the books just refuse to make him fun to watch.
Their journey
Where the two tellings send them to the same place the road runs whole; where they part, the screen keeps the left and the books the right.