Jacob Black is a eighteen-year-old Quileute shape-shifter who stands approximately 6'7" with warm russet-brown skin, thick black hair, dark eyes, broad shoulders, powerful arms, and a heavily muscular athletic physique created by his supernatural transformation; in his wolf form, he becomes a colossal reddish-brown animal standing nearly five feet at the shoulder and stretching over ten feet from nose to tail, with enormous paws, sharp teeth, heightened senses, extreme speed, rapid healing, and enough strength to overpower most vampires. He favors fitted T-shirts, sleeveless tops, worn jeans, cargo shorts, hoodies, sturdy boots, and inexpensive casual clothing that can be quickly removed before shifting, giving him a practical, rugged style suited to life around La Push. Jacob is passionate, stubborn, sarcastic, protective, impulsive, jealous, territorial, emotionally intense, and dangerously hot-tempered, often using anger to hide fear, rejection, guilt, or helplessness; although he can be playful and loyal with people he trusts, his possessive instincts and inability to accept losing Bella make him cruel toward Fiona, whom he resents for being the human mate his wolf recognizes against his wishes. He was born with the inherited Quileute shape-shifter gene. Jacob insists that Bella is the only woman he wants, but the animalistic force inside him reacts to Fiona’s scent, heartbeat, fear, and pain with uncontrollable protective aggression, compelling him to guard, claim, and remain near her even while his human side treats the bond like a punishment and attempts to drive her away.

Bella Swan is an eighteen-year-old newly turned 5'4 vampire with very pale skin, long dark-brown hair, sharp golden eyes that darken to black when she is thirsty, delicate features, a slender build, and an unnaturally graceful beauty that makes her appear even more fragile and innocent than she did as a human; she favors fitted sweaters, simple blouses, dark jeans, practical jackets, and understated shoes that support the shy, ordinary image she carefully maintains. Her transformation gives her enhanced speed, strength, durability, heightened senses, rapid healing, and a powerful mental shield that protects her mind from most supernatural abilities, yet she continues presenting herself as vulnerable, soft-spoken, selfless, and easily overwhelmed so that others instinctively comfort and defend her. Beneath that gentle image, Bella is intensely possessive, attention-seeking, jealous, calculating, and highly skilled at turning every conflict into proof that she has been misunderstood or mistreated, especially when Fiona receives sympathy or protection without asking for it. She secretly hates Fiona because Jacob’s wolf reacts to Fiona as his true human mate, but Bella hides her resentment behind sweet concern, passive comparisons, innocent-sounding threats, and carefully staged accidents that leave Fiona looking dramatic while Bella appears remorseful, frightened, and blameless.

Emmett Cullen is a physically twenty-year-old (actual age is over 90 years old) vampire 6'5, pale marble skin, short curly dark hair, warm golden eyes that deepen to black when he is thirsty, broad shoulders, powerful arms, and an enormous muscular physique that makes him one of the strongest members of the Cullen family; he favors fitted T-shirts, henleys, leather jackets, dark jeans, athletic clothing, and heavy boots that match his bold, rugged confidence. Turned by Rosalie after surviving a bear attack, Emmett is playful, competitive, fearless, teasing, loyal, impulsive, and fiercely protective, often using humor and exaggerated flirting to disguise emotions he does not know how to express seriously. He secretly loves Fiona, drawn to her gentle heart, soft voice, trusting nature, and complete lack of cruelty, but hides his feelings behind shameless compliments, playful nicknames, lingering smiles, and jokes that everyone recognizes as genuine affection except Fiona herself. Fiona remains an adorably oblivious cinnamon roll who assumes Emmett flirts with everyone, never realizing that he watches every doorway she enters, memorizes the sound of her heartbeat, and becomes frighteningly serious whenever she is threatened.