Trina

Trina is an antagonist in Big Hero 6: The Series. She is the android daughter of Obake who moonlights as a criminal bot-fighter.

Background
Trina appears to be a normal teenage girl, albeit with a controversial streak. In reality, she is an android controlled by Obake, whom she refers to as her father. Under the guise of a bot-fighter, Trina is sent out to gather intel on Hiro Hamada.

When not tending to her mission, Trina acts as an organized thief—despite Obake's disapproval. By hacking into the bots of her competitors and using them to steal from San Fransokyo, Trina orchestrates a crime wave that lets others take the fall while she ends up rich; for Trina, it's a profession that's both lucrative and fun. She's also obtained other knick-knacks such as figurines, which she keeps at her bot station in Good Luck Alley. Obake sees Trina's hobby of "collecting trinkets" as a waste of time.

Personality
Trina has a spunky, yet rebellious attitude. She addresses everyone she meets with snark (even her father) and acts in a very self-assured manner. Her effective cunning is partly responsible for her arrogance; she purposefully demeans herself so that others will let their guard down around her; in turn, this allows Trina to come off as innocent in spite of her snappy personality.

Trina shares Obake's disregard for the law and views villainy as freedom. Much like Hiro did in the past, Trina enjoyed the thrill of the bot-fighting ring, and the easy money that came along with it. However, her penchant for thieving went against her mission regarding Hiro, showing that she is capable of diverting from her directive despite her inherent loyalty to her "father".

Physical appearance
Trina is an adolescent girl, slightly taller than Hiro. In her human form, she has fair skin, back-length auburn hair and light blue eyes, matching Obake's. She dresses in a purple beanie, a pink short-sleeved shirt, and grey ankle-length jeans. She also wears black, fingerless gloves.

Role in the series
Trina first appears in "The Bot Fighter", where a string of bot-related crimes have plagued San Fransokyo. After discovering a connection between the bots being used in the crimes and the bot-fighting ring that he once participated in, Hiro goes undercover to Good Luck Alley to find information on the culprit (whom he believes to be Yama). While sleuthing, he sees Trina in the midst of a battle, which she loses. When Hiro tries to get into Yama's office, Trina stops him as she doesn't want Yama to cancel the fights due to Hiro's sudden arrival. When Hiro critiques Trina's bot, she ropes him into helping her improve it. The two begin to bond as they work together, with Trina noting that she's a self-taught fighter. She also claims to be such a fan of Hiro's that she researched his old fights as reference. When Trina asks why Hiro chose to quit, he simply contends that he's over bot-fighting. Trina nevertheless encourages him to continue if he enjoys it; this causes Hiro to steadily fall back into his old habits.

Over time, Hiro develops romantic feelings for Trina, which she apparently reciprocates. He eventually renters the ring as an official fighter and goes against Trina as his first opponent. Though she loses the fight, Trina compliments Hiro's skill and even gives him a kiss, apparently cementing a relationship. Meanwhile, Go Go, Honey Lemon, Wasabi and Fred sneak into Yama's office and learn that he isn't behind the crimes. This leads Hiro to deduce that Trina is the true culprit.

When Hiro confronts Trina, she admits to be the mastermind behind the crimewave and chides Hiro for being against her. Hiro confesses that his brother got him out of bot-fighting and encourages Trina to turn her life around, too. As she doesn't believe in reformation, Trina instead pressures Hiro to join her side, only to be foiled by the arrival of Big Hero 6. Unfazed, Trina summons a powerful killer bot to do away with the heroes while she slips away. Hiro tries to stop her, but his teammates' need for help forces him to let Trina escape.

Later, Trina regroups with Obake, who expresses contempt for her grand thefts. He demands to be shown something useful, to which she responds by relaying footage of Hiro confessing why he gave up bot-fighting. Though Obake shows animosity towards Hiro for refusing Trina's offer, he consoles his daughter and declares that it's time to move forward.

Trivia

 * Trina shares the same eye color with Obake, hinting at their ties.
 * She only addresses Hiro by his last name.
 * Trina is the second character Christy Carlson Romano voices in a series created by Mark McCorkle and Bob Schooley, who were the creative team behind Kim Possible, where Christy Carlson Romano played the leading role.