Sisu is the deuteragonist of Disney's 2021 animated feature film, Raya and the Last Dragon. For the majority of the film, she is the last of her kind. Sisu is a self-deprecating yet comedic water dragon, called upon by Raya to save humanity from a dark force known as the Druun.
Sisu is the last dragon of Kumandra. Legends say she's a divine water being of unspeakable beauty and unstoppable magic, but what Raya finds instead is a funny self-deprecating dragon who sees herself as the perennial C-student. Now she must learn to become the dragon of legend if she is to save the world with Raya.
Sisu is a kind and fun-loving dragon who loves making wisecracks and speaks in slang. While she is a bit of a goofball, she still is able to recognize when something is of serious consequence and will drop everything to help. She is shown to be somewhat naive as she does not understand the current human customs such as credit, hot sauce and thinks that most things can be solved with getting someone a gift. However, the latter is her strong suit as she retains her belief that one can be trusted through cohesion and unity. That is to say that she is much more trusting of others. Although she is quirky, she is wise and intuitive, able to give sound advice when required. She's brave, shown when she fearlessly fights the Fang armies' to defend Raya as well as at approaching Namaari holding a weapon despite the risk of her own life. She is loyal and open-minded, willing to give someone the benefit of the doubt for a chance to redeem themselves. A pure heart, she is forgiving and unable to hold a grudge towards anyone, even befriending Namaari after being revived by her siblings along with the rest of her kind, even though she accidentally killed her prior.
Sisu also demonstrates a certain level of omniscience, as demonstrated by her usage of anachronisms. For example, when describing herself to Raya, she compared herself to a C-grade student.
Sisu is a long, blue, spindly looking dragon with a darker shade on her back and a lighter shade on her stomach arms and face. She has short dorsal fins on her back and possesses white-bluish-violet hair as a mane and a small tuft of her at the end of her tail. She has big purple eyes, two dark blue horns on her head, and sharp teeth.
In her human form, Sisu resembles a young Southeastern Asian woman with long messy white-bluish-violet hair. She retains her purple eyes, but now has goofy looking teeth. She wears a blue, long sleeved robe with a design pattern on it and a white furry collar. Sisu wears gray-colored jeans that stop below the knees and blue soft shoes that reveal her ankles.
Sisu was always intended to die in the film, but there was debate regarding whether she and the other dragons should return. The decision to revive Sisu was largely the work of producer Osnat Shurer, who wanted a traditional Disney ending that “made your heart sing”.
Sisu exhibits traits of compulsive gift-giving, otherwise known as co-dependent gift-giving. Throughout the film, she believes that all of Raya's problems can be solved by giving Namaari a gift. While these behavioral tendencies are usually diagnosed as being for selfish reasons, Sisu's motives are genuine as she wants to help Raya save the world.
The word "Sisu" is a Finnish term that can be roughly translated into English as "strength of will, determination, perseverance, and acting rationally in the face of adversity. Sisu is not momentary courage, but the ability to sustain that courage." A concept that directly mirror's Sisu's brave and optimistic personality in the movie.