I truly believe in the headcanon that sonia and gundham have adopted himiko.
Not actually adopt tho, it's like your friend jokily adopting you. I think gundham and sonia would befriend himiko because one time, himiko showed them a magic trick because they were the only one willing to see. and when she did it, gundham was so shocked, enamoured, just so flabbergasted, that he declared that "Himiko is not one of mortals, she has power that befits the title of demon!" And Himiko (pre character development) wouldn't try to correct. 1, because she's too tired, and 2, she likes that gundham and sonia genuinely are interested and actively engaging in her "it's not tricks, it's maagic" Act.
This encounter is what made them friends. Sonia would kinda stalk himiko sometimes to talk to her, because she thinks himiko was very cool. And Gundham would basically beg for Himiko to show more magic tricks, to "show the Supreme Overlord of Ice the wicked magic of chaos and calamity, so that his eyes may be reminded of the dear nature of Netherworld!". Like.. while gundham encourages Himiko to go further into her passions (or delusions to other students), sonia supports himiko mentally, like offering her help and comfort during hard times.
I have a seperate hc that sonia helps gundham with homework a lot, and I shall connect these two hcs. Sometimes, when Himiko feels too tired to write an essay, or when Gundham doesn't understand, sonia hosts a tutoring session in her MASSIVE apartment, and tutors/encourages them. (it eventually turns into them goofing off and laughing at stupid shit they do)
This helps himiko, as she finally has friends who doesn't judge her, and match her energies (despite Gundham sometimes being too much for her). She finds herself becoming more confident and comfortable with them and other people.
This friend relationship catapults immediately into a parental relationship, as Sonia one day suddenly makes a suggestion that would involve "adopting himiko like our tuff evil daughter!" And Himiko wouldn't decline the offer, because the friendship from an outside standpoint really DOES look like a parental relationship. Like, Sonia and Gundham act like mom and dad watching their kid showing off something to them. Gundham is like a fun dad that keeps up with her and encourages Himiko to stay herself (to live the life that has been handed to your palms, as gundham would say it), and sonia is the supportive mother who would always help out and comfort Himiko when needed. Even with budget during Himiko's magic shows! (Like, after Himiko befriended them, her magic shows because even more extravagant and high quality, because of gundham's crazy suggestions and Sonia's huge funding.)
Gundham hearing this wouldn't be too sure about the idea, but thinking over the decision, he proudly agreed to be Himiko's dad due to "Her Power is only befitting to be from the spawn of The Supreme Overlord of Ice!", and him kinda viewing it like taking care of and loving an animal.
Their new development in their relationship wasn't really a secret, as Himiko would call sonia and gundham "Daddy" and "Mommy". many students found out and were VERY surprised at the situation. Tenko was definitely mad because "Your Dad is that degenerate male who acts like a degenerate villain?! Why couldn't it have been another girl??", and kazuichi would be distraught over "Miss sonia..? Being a mother to Himiko...? AND THAT STUPID HAMSTER DUDE IS THE FATHER?!!". I mean.. who would've thought that the princess with unconventional interests, and a crazy chuuni who wears red eye contacts, were parents to the kid that claims that her magic tricks are undeniably, 100% real?
I have nothing to write anymore,, but yeah I think they'd be really really cute.. I think Gundham would show Himiko the Devas when she's feeling down to lift her spirits. Or Sonia taking her on walks and exploring as mom and daughter. They sometimes huddle up and watch horror movies or serial killer documentaries, or go to various pet shelters and volunteer to help with troubles. She'd accompany Himiko to stores and malls, It'd be HELLA cute.
Please ladies and gentlemen and the gendernoncomforin gays, PLEASE hear me out on this. Please please please please please please please
