i mean listen. his most powerful form is a swan. he descends from the heavens to save rue from raven hell as a swan. he loves to do things of this sort.
also, there's something about how the heart shard of "hope" is what lets duck turn into a girl/princess tutu. and duck is... extremely (unintentionally but still) trans-metaphor-coded, in the way that her agab is duck but she is girl. she seems to really Hate being a duck (constantly describing herself as being "just a duck"), and spends most of her duck time floating sadly in water, trying to turn back into a girl, and sometimes spying on people because no one suspects a funny ducky. contrast Girl Time, where she's able to express herself much more freely, talk to her friends, dance, affect the plot, &c. she's like, a human therian, if there is such a thing.
so the heart shard of hope has the ability to transform you into an ideal/desired form. it's also, notably, the only heart shard whose form we never see - while we could assume it takes mytho's form like all the other heart shards, it could also very well be princess tutu herself, or Girl Mytho, or an entire swan. we just don't know! it's not very hard to read it as some kind of gender heart shard for swan-adjacent genders (at least, not if you're just posting for fun).
in light of this, i think it says... something, that mytho gets to transform into a swanboy prince, and subsequently a full on glowing swan that saves your life from raven hell, once he gets this heart shard back. it's not just his full heart being back, either - duck also gets to transform into a swan, or be perceived as a swan, on several occasions, so it's specifically hope shard doing it. is mytho a therian? idk, i just think there's something about him and his heart shards. he could be. it would be fun. we should let him be a swan for a while maybe
In general European folklore, a "swan maiden" is a sort of therianthropic animal-woman, similar to selkies.
The selkie:
A typical folk-tale is that of a man who steals a female selkie's skin, finds her naked on the sea shore, and compels her to become his wife.[17] But the wife will spend her time in captivity longing for the sea, her true home, and will often be seen gazing longingly at the ocean. She may bear several children by her human husband, but once she discovers her skin, she will immediately return to the sea and abandon the children she loved.
The swan maiden:
The folktales usually adhere to the following basic plot. A young, unmarried man steals a magic robe made of swan feathers from a swan maiden who comes to bathe in a body of water, so that she will not fly away, and marries her. Usually she bears his children. When the children are older they sing a song about where their father has hidden their mother's robe, or one asks why the mother always weeps, and finds the cloak for her, or they otherwise betray the secret. The swan maiden immediately gets her robe and disappears to where she came from.[10] Although the children may grieve her, she does not take them with her.[11]
Much like the typical folkloric werewolf, these figures require some kind of pelt or garment to transform into animals, suggesting that their "core" form is human. Yet whereas the werewolf often lives most of their life as a human man and prefers it that way, the selkie and the swan maiden prefer to live as animals, disrobing into human form only to bathe. The act of a man stealing a maiden's animal-skin to make her his wife, then, is easily read as an act of patriarchal violence. It could also, if one chooses, be adopted as a metaphor for forcing a body and/or identity that is fluid or otherwise non-normative into a closet labeled "a good, submissive wife." (The swan maiden stealing back her skin, when she is the protagonist and not the hunter, becomes a feminist story; can it also be a lesbian or asexual story, a masculine or genderqueer story, an intersex story?)
As for cartoons for children... isn't Fakir and Kraehe attempting to stall the return of Mytho's heart, convince him that he doesn't need a heart, etc, a little like the hunter keeping the swan maiden away from her swan-skin?
boy swan maiden mytho theory... beautiful and true and evergreen. there is something very, very queer and feminist to the nature of the swan maiden... on a somewhat related note, it seems likely that princess tutu (both the show and duck-as-tutu the character) are inspired by the swan maiden and her children as seen in one of the stories in dolopathos (there is no short title for this story...)
"A nameless young lord becomes lost in the hunt for a white stag and wanders into an enchanted forest where he encounters a mysterious woman (clearly a swan maiden or fairy) in the act of bathing, while clutching a gold necklace. They fall instantly for each other and consummate their love. The young lord brings her to his castle, and the maiden (just as she has foretold) gives birth to a septuplet, six boys and a girl, with golden chains about their necks. But her evil mother-in-law swaps the newborn with seven puppies. The servant with orders to kill the children in the forest just abandons them under a tree. The young lord is told by his wicked mother that his bride gave birth to a litter of pups, and he punishes her by burying her up to the neck for seven years. Some time later, the young lord while hunting encounters the children in the forest, and the wicked mother's lie starts to unravel. The servant is sent out to search them, and find the boys bathing in the form of swans, with their sister guarding their gold chains. The servant steals the boys' chains, preventing them from changing back to human form, and the chains are taken to a goldsmith to be melted down to make a goblet. The swan-boys land in the young lord's pond, and their sister, who can still transform back and forth into human shape by the magic of her chain, goes to the castle to obtain bread to her brothers. Eventually the young lord asks her story so the truth comes out. The goldsmith was actually unable to melt down the chains, and had kept them for himself. These are now restored back to the six boys, and they regain their powers, except one, whose chain the smith had damaged in the attempt. So he alone is stuck in swan form. The work goes on to say obliquely hints that this is the swan in the Swan Knight tale, more precisely, that this was the swan “quod cathena aurea militem in navicula trahat armatum (that tugged by a gold chain an armed knight in a boat).”"
the swan children in this story, unlike their mother, appear to prefer their human form to their animal one, with their "core" form being the animal one. also, specifically the daughter, with her transforming trinket, acts as the main agent of the plot and disruptor of the status quo once the chains of her brothers are stolen. much like duck, in cartoons for children, is the disruptor of the status quo who returns mytho's heart shards and eventually his transformation item to him. also, lohengrin (knight of the swan) reference. we all know princess tutu's tendency to partake of the lohengrin reference.
(also, even in stories where patriarchal violence isn't directly and immediately visited on the swan maiden, someone else conspires to sabotage her and make her suffer... hmm. don't know what it is about that, but there is something.)
