|Affiliation||Hogwarts School of Witchcraft and Wizardry|
Kai Chang (b. 1998) is the half-brother of Cho Chang by Cho's father. He attended Hogwarts School of Witchcraft and Wizardry from 2009 to 2016.
On the first of September in 2009, he befriended Violet Parkinson, Teddy Lupin and Dewey Diggory aboard the Hogwarts Express. The four agreed to remain friends through their schooling regardless of which Houses they joined.
He rode with Dewey across the Black Lake, and told Diggory that Cho had been submerged in the Lake dor the Second Task of the 1994-1995 Triwizard Tournament, before realizing that Dewey's late brother had been the Champion sent to rescue her. Before being Sorted, Kai was recognized by Deputy Headmaster Horace Slughorn as a relative of Cho's. He then partook in the infamous Sorting of 2009, and was placed in Ravenclaw, where he roomed with Rodney Bode, Connor McCormack, and Gilbert Zirkle.
Following the Sorting, Kai spoke up against Saul Rambleston's accusation that several of the first-years weren't "quite as Ravenclaw as [they] should be." His boldness was rewarded by an older student forcing him to answer the dormitory guard's riddle: "A student stands atop the highest mountain in the world. How can she go higher?" Kai successfully responded that she could go higher "by reaching for enlightenment." That night, Kai discovered why McCormack was so distraught about being separated from his sister when he learned about their parents.
The next morning, Kai explained the McCormack's story to Lupin during Transfiguration, costing both Houses five points for talking in class. He later lamented Zirkle's inquisitiveness, and questioned whether Gilbert really belonged in Ravenclaw. During double flying lessons with Hufflepuff, Chang and Diggory agreed to help each other's Housemates in an "inter-House cooperation" effort – Kai aided Sung-Hee Moon ad Alduin Beauxjour – earning twenty points each from Coach Mannock. On the third day of flying classes, Chang got into an argument with Beauxjour over Chang's tutoring ability; when Alduin insulted Kai's sister and Dewey's brother, the three got into a fight that cost both Houses fifty points, and landed the three in detention.
The three served their punishment with Argus Filch by cleaning, oiling and polishing a room full of "horrendous medieval devices" in the dungeons. When Filch caught the three of them talking, he split them up, instructing Chang to clear out a shadowy alcove that contained a marble bust of Mrs. Norris. After the three were finished their detention duties, Chang was nearly attacked when Beauxjour accused him of stealing his wand, but Diggory broke up the altercation. A search of the dungeons failed to turn up Beauxjour's wand, and he remained firm in the belief that Chang stole it.
Along with Lupin and Diggory, Chang helped in escorting Parkinson to classes after Lupin caught Roger Drocker and his friends picking on her. He was later paired with her in a double Charms class with Slytherin, learning that Ophilia Karait was having trouble controlling her House given that Slytherins were unanimously suspected for the rash of wand thefts. Parkinson also informed Chang that he was arrogant when he told her that he'd questioned Zirkle's placement, but after Stephen White's wand was stolen, Chang told Zirkle not to go anywhere alone. He was one of the first to see Nagaeena Indrani immediately after she was attacked with a Hair-Removal Jinx.
Toward the end of October, Kai was enlisted by Lupin to help prepare a surprise birthday party for Parkinson. When Lupin discovered the Room of Requirement, Chang explained to him what he had found, having heard of the Room from Cho. On the night of Violet's birthday, Chang, among the other guests, was retrieved by Decima Caul and taken to the Great Hall where he was among the first to see Violet spellotaped upside-down to the Slytherin points-hourglass. He tried to deny involvement in the prank, but was largely ignored.
During the Gryffindor/Slytherin Quidditch match, Chang explained the particulars of the game to Zirkle. When Diggory later suggested that Headmistress Llewellyn might interrogate students using veritaserum, Kai explained that the Ministry of Education wouldn't allow it. He tried to help Lupin understand why Parkinson wanted nothing to with any of them after the attack on her birthday, and was with Lupin and Diggory when the three discovered that Chloe Grey had facilitated the attack by telling Roger Drocker that Parkinson was going to be in the seventh floor corridor on the night of 30 October. In the process of Lupin telling Grey off, Chang and Diggory discovered Teddy's metamorphing abilities, and were sworn to secrecy.
When Lupin began descending to the Slytherin dorms and enduring daily hexing in an effort to talk to Violet, Chang attempted to talk him out of it, and helped Diggory carry Lupin to the Hospital Wing. He sent Parkinson a note reading "We're all really, really sorry!" in an attempt to get her to talk to Lupin so that he would stop going to the Slytherin dorms, and tried unsuccessfully, along with Diggory, to physically stop Lupin. When Violet did finally agree to talk to Lupin, Kai and Diggory were waiting at the top of the stairs for them.
Chang became increasingly proficient in Charms, earning five points for levitating a pillow, and losing those points for using foul language after being hit by a textbook flung by Bernice Selwyn. He was the first to learn that Parkinson wasn't going home for Christmas, and later argued with Diggory over which team would win the upcoming Ravenclaw/Hufflepuff Quidditch match. He started calling Violet "Vi" to her annoyance, and was asked by her, on Indrani's behalf, to ask Zirkle to stop following Nagaeena. He later admitted to having considered the possibility that he had been misplaced during Sorting, and revealed to Lupin and Diggory that Parkinson would be staying at Hogwarts over the holiday. After Hufflepuff beat Ravenclaw in Quidditch, Kai bemoaned the fact that Ravenclaw's Seeker had lost the Snitch because he'd been distracted when his Wand Alarm went off.
In December, he was the third, following Lupin and Diggory, to ask Violet if she wanted to spend the holiday with his family, though he did so with an utter lack of tact that upset Parkinson. On the second-to-last day before the holiday break, Kai met with Lupin, Diggory and Parkinson in the Room of Requirement to exchange gifts. Heading downstairs afterward, the four of them witnessed the attempted theft of Colleen McCormack's wand, and Kai was sent sprawling when he was run down by the invisible thief; Kai later recalled that he thought he could see someone if he squinted and turned his head sideways.
Moments later, Chang saw both McCormacks, two Ravenclaws and three Gryffindors barrel into the Hall firing spells, some of which hit students, including Clarice Darcy, down the stairs from the Entrance Hall. In the midst of the commotion, Chang pulled Violet to safety, and took refuge with her, Lupin and Diggory in a classrom down the corridor as a full-scale riot erupted in the Hall. When the sound of the riot subsided, Chang waited with Violet while Lupin and Diggory made sure the Hall was clear before reutrning to Ravenclaw Tower. The next day, Chang was among the first students to be questioned by the Headmistress, and suggested his theory that an Invisibility Spell or Disillusionment Charm had been used by the perpetrator. Later in the day, he was picked up in Hogsmeade by his sister.
Following the Christmas holiday, Kai was dropped off at the King's Cross Station by Cho and her fiancé, and met u pwith Lupin and Parkinson to ride the Hogwarts Express back to school. Kai met Harry Potter, who had accompanied Teddy and Violet, announced his sister's engagement, and awkwardly suggested that Cho invite Harry to her wedding. His sister also called him by his nickname of "Little Owl" to his embarassment, and Parkinson used the information as leverage to get Kai to stop calling her Vi. The three discussed their holiday on the trip back to Hogwarts, and Parkinson sarcastically thanked Chang for the Exploding Wand he'd given her. Kai also told Teddy and Violet that Cho being engaged to a Muggle was weird, and that his while their parents didn't disapprove, they weren't enthusiastic either. He told them excitedly about the variety of Muggle things he'd experienced over the holiday, then discussed the precariousness of Headmistress Llewellyn's position.
When Guy Blake was caught with a pistol after the implementation of the Zero Toleration Policy in January of 2010, Kai explained to his roommates that a handgun is "a Muggle weapon, like a wand, except instead of shooting spells it shoots flaming pieces of metal." Chang was one of the first people that Diggory and Mercy Burbage told about their support group idea, and was present for the double Potions class with Hufflepuff in which Ophilia Karait substituted for Professor Slughorn and tricked the class into believing that they had to identify poisons by taste. He lost Ravenclaw twenty points for asking if Karait was "barking," another twenty for talking with Diggory while the class was supposed to be reading, and another twenty points for insolence. During the class, Kai noticed Zirkle glancing at Karait, and questioned Gilbert's infatuation with "snakey Slytherin girls." He nearly interceded on Zirkle's behalf when he believed that Zirkle had ingested a poison for which Karait refused to give him the antidote.
When Chang learned about and the Marauder's Map from Lupin, he claimed that Slipfang sounded like a goblin name, losing ten points for his House for talking during Transfiguration class. Chang was later informed by Parkinson to meet at the Room of Requirement, and witnessed Mortimer Thickwaite and Clarice Darcy exiting the Room. Inside the Room, he learned that Lupin had nearly been expelled for using Paralyzing Potion, and got to see the Marauder's Map, suggesting that Slipfang had been using the secret tunnels to enter Hogwarts. When Diggory brought up his support-group idea, Kai questioned how to get Slytherins interested in something that wouldn't directly benefit them, but agreed to support the group on the grounds that every House had had someone expelled under the new Policy.
Chang suggested using a curse to swear potential group members to secrecy, but Lupin pointed out that none of them knew any curses. Kai recruited Zirkle, McCormack, Deana Forte, and Aisha Allouzi from his House, and on the third Friday in January, he attended the first meeting of the reorganized D.A. He witnessed the reconciliation between Parkinson and Grey after a tense confrontation, and was present for the meeting in which Lupin revealed his "Who is Slipfang?" poster and discussed the unfair expulsion of several students, particularly Geoffrey Montague, under the Zero Toleration Policy. After the meeting, Chang asked Parkinson what she had said to Grey following their confrontation, but Parkinson insisted that it was none of his business.
Several days later, Chang recruited Zirkle, McCormack and Forte to accompany him to the Room of Requirement to pick up posters, and the four joined eleven other D.A. members in papering the school with Slipfang posters. For the group's second round of posters, Chang and Diggory papered the Quiditch pitch with fliers, but they were caught by Coach Mannock and assigned three days of detention. They served their punishment – cleaning out the space beneath the bleachers of the Quidditch pitch – alonside Lupin, Hayes, Hargrave, Grey, Burbage, Dreadmoor and Zirkle.
Along with twenty-two other D.A. members, Chang signed the letter of protest that Lupin, Parkinson and Burbage had drafted. Three days later the letter was printed in the Daily Prophet and the Quibbler in the same issue as a letter from S.C.O.U.R.G.E., though Chang had never heard of the organization. Chang received a letter from his parents concerning his involvement in the D.A., telling him to behave and make sure he didn't get into any trouble. He simply laughed off the hate mail he received in regards to the letter of protest.
Kai was among the first to see the Room of Requirement on Valentine's Day, when Burbage, Moon, Susan Smith and Karen Lee decorated the entire room in varying shades of pink, and though horrified, he tried to encourage Burbage's effort. During the meeting, he jokingly suggested that the D.A. enchant Hogwarts Castle pink, but Lupin latched onto the idea as a reminder of Dolores Umbridge. Kai wound up in a playful mass-duel between students casting Color Change Charms at one another, and acquitted himself rather well. That following Sunday morning, Kai, along with the rest of the D.A. members, got a valentine from Burbage and Moon in the Great Hall.
Chang, along with Diggory, Parkinson, volunteered for what became known as "the Pink Protest," but was confronted by the Grey Lady while casting charms in the sixth floor hallways. When he realized that she wasn't turn him in, he continued on, heading to the kitchen entrance when he was finished. There he met Parkinson, and the two were joined by Lupin, who had taken the form of Professor Flitwick; Chang was worried to see Flitwick, but later claimed to have known all along that it was actually Lupin. He and Parkinson waited outside the kitchen while Lupin, as Flitwick, entered to order the kitchen-staff of House-elves to take the weekend off, then headed back upstairs with Lupin and Parkinson to see the banner that Diggory and Burbage had hung in the Great Hall reading: "In Thanks for Their Loyal Service, the House-Elves Have Been Given the Weekend Off, Courtesy of the D.A."
Before leaving the Great Hall, Lupin checked the Marauder's Map, and the group spotted Slipfang in the dungeons. Chang suggested checking him themselves, and Lupin agreed, heading for the dungeons. Chang was accompanied by Parkinson while Lupin was accompanied by Diggory, and the four of them cornered the invisible wand-thief in a corridor before Kai cast an aparecium charm that revealed the goblin wearing a hooded cloak. Slipfang responded by casting a curse against Chang that struck him like a whip, after which Diggory and Lupin attacked the goblin and Parkinson ran for Professor Slughorn. She and the professor returned in time to save Chang, Diggory and Lupin.
Kai was transferred to the Hospital Wing with Lupin; since his injuries were less severe than Teddy's, his treatment was delayed, but Madem Pomfrey, Professo rLongbottom, Professor Rai, Professor Peasegood, Professor Slughorn and Headmistress Llewellyn were all unable to identify the spell that Slipfang used on him. Pomfrey said only that it looked like a whip had nearly flayed him open; the wound burned like fire, and was only moderately alleviated by an ointment administered by Pompfrey.
Later that night, Chang saw Harry Potter again when Potter visited Lupin, and explained to him the series of events that led him and Lupin to the Hospital Wing. The next night, he and Lupin were visited by Potter, Diggory, and Parkinson, and Violet returned Kai's glasses, which had been shattered in the altercation with Slipfang. Chang cast an occulus reparo to fix the lenses.