Sirius

Biodata

Feature	Details
Name	Sirius Black (西里斯)
Alias(es)	Padfoot 12 14
Species/Race	Wizard; Animagus with a black-dog form 25
Gender	Male
Affiliation	Hogwarts School of Witchcraft and Wizardry; Gryffindor House; the Marauders 12 14
Occupation/Role	Sixth-year Hogwarts student; Marauder 14
First Appearance	Chapter 10 10

Background / History

Sirius was raised under the Black family's blood-purity ideology, where he was taught that bloodline and family honour outweighed everything else. At Hogwarts, however, his friendship with James Potter, Remus Lupin, and Peter Pettigrew led him to value chosen bonds above his family's expectations. He believes this choice may cost him his inheritance, name, and family. 31

His relationship with the Black family is strained. Kreacher calls him a traitor and a disgrace for taking a Black family treasure to an outsider, while Sirius dismisses this hostility as typical of his family. 41

At Hogwarts, Sirius helps develop the Marauder's Map with James and Remus. He and James are also unregistered Animagi, using their animal forms to protect Remus during his full-moon transformations. 14 25

Appearance

Sirius closely resembles his younger brother Regulus, though his expression is more relaxed and openly mischievous. He has gray eyes and ordinarily does not care much about untidy hair, wrinkled robes, or mud on his boots. 30 41

• Gray eyes that appear bright in moonlight. 31
• Strong physical resemblance to Regulus Black. 30
• Animagus form: a large black dog. 25
• Makes an unusual effort to neaten his hair, robes, and boots when preparing to meet Lucretia. 41

Personality

Sirius is irreverent, quick-tempered, and deeply mischievous. He readily trades insults and physical scuffles with James, participates in pranks, and treats authority with open impatience—behavior that repeatedly earns him detention and costs Gryffindor points. 12 14 43

Behind that recklessness, Sirius is intensely loyal. He risks injury to restrain Remus during a dangerous full-moon transformation, keeps sensitive secrets for his friends, and takes threats against Lucretia seriously even when it requires cooperating with Barty Crouch Jr. 25 31 34

Sirius is also emotionally transparent when provoked. His growing feelings for Lucretia show through jealousy, protectiveness, and unusually careful gestures, such as tracking her safety, delivering gifts, and remembering her Butterbeer preference. He nevertheless rejects James's treatment of her as a romantic “prize.” 29 35 40 42

Abilities & Skills

Animagus Transformation

Sirius can transform into a large black dog, allowing him to physically intervene during Remus Lupin's werewolf transformations. 25

• Works alongside James's stag form to redirect and restrain Lupin's werewolf form. 25
• Endures injuries while shielding Lupin from self-harm and attacks. 25
• His dog scent is noticeable enough for Lucretia's cat, Luna, to react aggressively even while Sirius is concealed. 36

Defensive Magic

Sirius considers Defense Against the Dark Arts one of his stronger subjects and is familiar with the more practical, dueling-focused sixth-year curriculum. 40

• Uses Lumos Maxima to guide Lucretia through unlit corridors after curfew. 31
• Offers to help Lucretia with Shield Charms and other protective magic. 40
• Participates in the protection plan against the threat connected to Peter Pettigrew. 34

Herbology and Potion Assistance

Sirius develops a practical interest in Herbology and potion-making because of Remus's condition. 37 42

• Skillfully handles Venomous Tentacula with Remus during Herbology. 18
• Learns how the preparation of potion ingredients can prioritize a werewolf's lucidity over soothing effects. 42
• Assists Lucretia in preparing a potion intended to help Remus retain consciousness during transformations. 42

Stealth and Surveillance

Sirius is experienced in moving through Hogwarts covertly and coordinating with the Marauders. 30 34 41

• Uses the Marauder's Map to track Lucretia and identify potential threats near her. 30 34
• Uses the Invisibility Cloak during surveillance and follows Lucretia into the Forbidden Forest out of concern for her safety. 32 36
• Coordinates with James through a Two-way Mirror during the East Tower operation. 41

Equipment / Weapons / Items

• Wand — used for illumination, spellwork, and everyday magic. 17 31
• Marauder's Map — jointly developed with James and Remus; used to track people throughout Hogwarts. 14 29 34
• Invisibility Cloak — used with James for covert observation and protection. 32 36
• Two-way Mirror — used to maintain contact with James during covert operations. 41
• Silver Star-Guiding Compass — an intricate Black family treasure bearing constellation patterns; Sirius obtains it from Kreacher intending to give it to Lucretia. 41
• Ancestral Compass — lends Lucretia a Black family compass for Astronomy study. 46

Relationships

• James Potter — Best friend and fellow Marauder. Their bond is built on pranks, arguments, and mutual support; James relentlessly teases Sirius over Lucretia. 14 25 35
• Remus Lupin — Close friend whom Sirius protects during full-moon transformations. Sirius also helps prepare remedies to preserve Remus's consciousness. 25 42
• Peter Pettigrew — Fellow Marauder whose secret surveillance of Lucretia and the Crouch family causes Sirius to distrust him. 29 34
• Regulus Black — Younger brother. Their relationship is tense but retains warmth through shared childhood memories and their mutual concern for Lucretia. 34 46
• Lucretia Crouch — A growing personal attachment marked by protectiveness, trust, jealousy, and mutual openness. Sirius promises to safeguard her secrets and asks her to call him by his first name in private. 21 31 40 42
• Barty Crouch Jr. — Uneasy rival and temporary ally. Despite mutual suspicion, they cooperate to protect Lucretia from the threat surrounding Pettigrew. 12 34
• Severus Snape — Long-standing rival whom Sirius calls “Snivellus”; Sirius openly distrusts Snape's interest in Dark Magic. 42
• Lily Evans — James's frequent target of affection. Sirius delivers Lucretia's cinnamon apple tart to Lily, though he is visibly jealous of Lucretia's attentiveness toward others. 40

Story Role / Major Arcs

Early Hogwarts Term

Sirius is introduced as one half of Gryffindor's notorious troublemaking duo with James. Their public fight during the opening feast inadvertently shifts attention away from Lucretia, allowing her to eat without being scrutinized. 12

Protecting Remus Lupin

Sirius joins James in their Animagus forms during Remus's transformation at the Shrieking Shack. When Remus becomes far more violent than usual, Sirius's black-dog form helps keep him from severely harming himself despite suffering injuries in the process. 25

Growing Connection with Lucretia

Sirius begins acting on his concern for Lucretia by shielding her from Peter's intrusive attention, escorting her through Hogwarts, and taking her warning about a “rat” seriously. Their trust deepens when he promises to keep Sophia's premonition confidential. 21 30 31

Pettigrew Surveillance Alliance

After discovering that Peter has been recording information about Lucretia and Mr. Crouch, Sirius joins James, Remus, Regulus, and Barty in a temporary alliance. Sirius proposes using the Marauder's Map for remote monitoring while Barty and Regulus provide closer protection. 34

East Tower Potion Work

Sirius secretly plans to deliver Lucretia a Black family compass and Butterbeer while she works on Remus's potion. In the classroom, he assists her with ingredients and demonstrates a more thoughtful understanding of potion-making and Remus's suffering. 35 41 42

Black Brother Reconnection

Sirius reluctantly joins Regulus and Lucretia on the Astronomy Tower. Their shared lesson with the Ancestral Compass prompts Sirius and Regulus to recall childhood moments together, revealing that their sibling bond has not fully disappeared. 46

Notable Quotes

“At Hogwarts, I met James and the others. I discovered some things are more precious than blood.” 31

“She's a person, not a pickup line.” 36

Trivia

• “Padfoot” refers to Sirius's black-dog Animagus form. 25
• Sirius calls James “Prongs,” Remus “Moony,” and Peter “Wormtail.” 14 21 30
• He claims that the Black family motto is “Always Pure.” 31
• Sirius is unnerved by Lucretia's cat Luna reacting to his dog scent, inspiring James's teasing that “Padfoot” fears kittens. 36