Big Hero 6 Wiki

As you get older, things change and sometimes people move away. Before I know it, you'll be old enough to head out on your own, and sure, I'll be sad, but we'll always be family.

Cass is a supporting character in the Big Hero 6 franchise. She is the hard-working and supportive loving aunt of Hiro Hamada and the late Tadashi Hamada, as well as the owner of the Lucky Cat Café.


Cass is a relative of Hiro and Tadashi's parents. Since her youth, she has lived in San Fransokyo and was friends with Diego Cruz, frequently visiting Joe's Diner with him until one day Cruz moved out of town. During her college days, Cass played softball and became quite athletic due to it[2].

Following the death of Hiro and Tadashi's parents when Hiro was only 3 years old, Cass became the children's guardian and took them into her care. The three of them lived in Lucky Cat Café where Cass also worked, and some time when Hiro was still a toddler, Cass got a new cat who was named Mochi[3].

For the following ten years, Cass raised both of her nephews as best as she could despite admitting she lacked parenting knowledge and often worrying about not doing a good job, though both Tadashi and Hiro assured her otherwise.

Official Description

Cass is the overworked but always-supportive guardian of brothers Hiro and Tadashi. The owner of a popular San Fransokyo bakery and coffee shop, Aunt Cass is proud, ebullient and thinks the world of her two genius nephews. She's always good for a laugh and ready with a hug, tirelessly there for support and a great home-cooked meal.[4]


Cass is a caring woman who loves her nephews above all else. She is very loving towards them but knows when to be strict and firm when necessary. This is shown when she picks them up after they are released from prison. She hugs them and asks if they are okay before lecturing them about how much they worried her.

Cass seems very excitable, talkative, and is usually in a happy mood. Cass is also very business-savvy and hardworking from managing restaurant and home simultaneously, which has rubbed off into her firm but motherly nature. She is also understanding and did what she could to help Hiro through his depression after Tadashi's death.

She supports and encourages the decisions of Hiro and Tadashi while wanting what is best for them, as she encourages Hiro to go to college as it is what Tadashi would have wanted. She is proud of her nephews and is not afraid to show it. However, she also appears to be rather oblivious, as Hiro was able to hide Baymax from her and sneak out together, and later on, keep their activities with Big Hero 6 a secret despite some clear hints.

Cass also has a creative streak, which she integrates into her work. As a talented chef, she can make many delicious dishes that have a great reputation for the regulars at her restaurant. She also comes up with special events held at the café to attract new customers, such as poetry readings because of her love for poetry. Additionally, Cass is athletic and likes to work out. This also helps at her job as she is able to move with agility to take orders, serve food and carry the dishes, especially when there are many customers at her shop.

In Baymax!, it is revealed that Cass feels as if she has to work tirelessly in order to take care of her family. It's also revealed that she has a good relationship with the frequent customers at Lucky Cat, such as Sayaka, but fears that taking days off would mean her clients will go away permanently. Yet, Baymax eventually helps her overcome these feelings.


Cass is a Caucasian female with green eyes and wavy brown hair. Typically tied to her home which doubles as a cafe, Cass usually wears comfortable and casual clothing: her main apparel being a simple short-sleeved v-neck and a pair of capris, topped off with an apron when on the job and a silver-turquoise necklace that she never seems to go without. She also wears a pair of red flats.


When Hiro and Tadashi get arrested on charges of involvement with bot-fighting, Cass pays for their release and comes to pick them up at the police station. She hugs them and asks if they are alright, then proceeds to take the two by ear and chastises them about how worried she was for them and their irresponsibility. The family returns home to the café, where Cass scolds them about the lengths she has gone to raise them as best as she could and begins stress eating to calm herself down as she departs upstairs with Mochi. After hearing her speech, Tadashi tries to talk Hiro out of bot-fighting before Aunt Cass eats everything in the café from stress.

Soon, Hiro decides to enroll into San Fransokyo Institute of Technology and spends the next few months working on his admittance project; Cass takes care of Hiro when he gets exhausted during the run. When the university's convention rolls around, Cass attends the convention with Hiro, his friends Go Go, Wasabi, Honey Lemon, and Fred, and Tadashi to support Hiro, where she tells him how proud she is of him and Tadashi after Hiro's presentation display. In celebration of Hiro's acceptance into the Institute, she offers to cook dinner at the café for the party free of charge. Tadashi asks her if he and Hiro can have some time by themselves, telling her they will catch up and she accepts. However, shortly after she goes to the car with everyone else, a fire starts at the convention hall, which takes Tadashi's life.

Along with Hiro and the others, Cass attends his funeral and holds a memorial for Tadashi at the café. Cass mourns Tadashi's death and is comforted by Hiro's friends. However, for Hiro, he falls into a deep depression; during this time Cass tries her best to make Hiro feel better and brings him his food though Hiro is too upset to eat. She tries to console Hiro and convince him to register for classes at SFIT as that it is what Tadashi would have wanted, but Hiro refuses to budge and she decides to give him space. A while later, when Hiro notices Baymax leaving his room to track where the microbot is leading, Hiro follows but runs into Cass before he can exit the café. He lies to her by saying he is going to register for classes and she hugs him, happy to see Hiro is finally out of his room and going to apply for college. Cass says she will prepare wings for a special dinner in celebation of Hiro's "first day at college". She gives him another hug before letting him go.

When Hiro returns home after nearly being killed by Yokai and trying unsuccessfully to report the incident to the police, Cass notices he is home and is already preparing the dinner and wants to hear about it. However, Hiro dodges this by saying that he has a lot of homework and assignments to catch up on from college and takes the wings to his room to hide Baymax from her. Hiro then sneaks past her while she is watching Frankenstein to go to the garage to create armor for Baymax and download a fighting chip so Baymax can fight Yokai.

Baymax's body was lost during their battle, but Hiro and his friends defeat Yokai and have him arrested. Following this, Cass prepares a lunch for Hiro as he heads off to SFIT with his friends; Hiro and Cass hug, though Hiro asks for one last hug as he takes the lunch she prepared and leaves for the college with her smiling as she watches him leave.

After Hiro's acclimation to college, he rebuilds Baymax and both go to Lucky Cat Café where Baymax helps Cass in picking up a lot of dirty dishes, then Cass becomes happy to see the robot again. She is also seen in a newspaper photo attending a ceremony of a building dedicated to Tadashi alongside Hiro, Baymax, Mochi, and the other members of Big Hero 6.


Hiro Hamada

Cass is Hiro and Tadashi's aunt. Hiro tends to stress her out and cause her to "stress eat" due to his illegal bot fighting, though she loves him nonetheless and vice versa. She is very supportive and proud of his abilities and was overjoyed when his Microbot exhibition won him an invitation to attend the San Fransokyo Institute of Technology.

Like Hiro, she also mourned Tadashi's death. She would bring food to Hiro after Tadashi's death as Hiro fell into a severe state of depression and refused to leave his room for two weeks. She tried to encourage him to go to college because Tadashi would've wanted it and she wanted him to recover, but he remained silent and she decided to give him space. When Hiro left his room for the first time in two weeks and he lied about going to register for classes (he was really going to catch up to Baymax), she was overjoyed and hugged him.

Overall, the two have a positive relationship and are close, especially since now they are the only known close relatives each other has. However, it is interesting to note that Hiro is keeping his superhero persona a secret from her. This is most likely because she has been shown to worry about Hiro and disapproves of him doing dangerous activities (such as bot fighting) and after Tadashi's death, she might forbid him to continue being a superhero as it would put his life at risk.


Though in the first film, she appeared oblivious to Baymax's existence, in "Baymax Returns," she is happy to see him and says, "He's back," implying that either Hiro or Tadashi introduced the robot to her at some point (likely during the time Hiro was building his Microbots with Tadashi and their friends due to the many group pictures they took).

Still, Hiro has to be careful so that Baymax does not accidentally reveal their superhero identities to her.

Go Go, Wasabi, Honey Lemon, and Fred

Cass has basic and friendly relation with Hiro's friends. However, after Tadashi's death, they attend his memorial at her home and comfort her during the hard time. Arguably, Go Go can be considered one of Hiro's friends that Cass is most close with.

Tadashi Hamada

Cass had raised Hiro and Tadashi for a decade since their parents died, though she admits she is not perfect. However, Tadashi hated making her upset and tried his best to make her proud, encouraging Hiro to do the same.


  • Early stages of the plot and a 2013 video from Rotoscopers reveal that Cass was originally portrayed as Hiro and Tadashi's mother rather than an aunt. This was closer to the Marvel Comics version of Big Hero 6, where Maemi Takachiho was Hiro's widowed mother.
  • Concept art and some 3D renders for Cass depicted her with white hairstreaks and a tattoo on her arm. Though both of these elements were removed in her final design, she can be seen still with both in the film's credits sequence.
  • Cass makes a cameo in Wreck-It Ralph 2 on an advertisement that reads "Sassy housewives want to meet you today!"



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Aunt Cass.


  1. It is not officially confirmed that her last name is actually "Hamada", but some translations and media utilize it as such.