Re these questions:

 - https://japanese.stackexchange.com/questions/93904/how-does-last-name-kun-compare-to-1st-name-san

 - [(Danganronpa) Why does Naegi call Togami "kun" and Aoi "san"?][1]

- [(Kaguya-sama) Why does Chika call Miyuki as 'kun'/'chan' but Kaguya 'san'?][2]

**Scope**: Actually my ideal is to ask this generally, but I think it's too big. I'm gonna limit asking to high school students, which is really my main target because I'm asking these re anime/manga which mainly feature high school students anyway. (For now, I'm just going to forego thinking about this for the anime/manga characters that are 20+.)

**Question**: Suppose student Ashanti Tanaka calls student Bidatz Mikoto as Mikoto-san. **How relevant is the gender** of Ashanti or Bidatz for if later Ashanti would later "upgrade" to call Bidatz as Bidatz-san or Mikoto-kun/chan (but not Bidatz-kun/chan)?

- Somehow, I suspect Japanese boys will upgrade calling other Japanese boys from last name-san to last name-kun but will upgrade calling Japanese girls from last name-san to 1st name-san. Idk. I know age factors in here, but my question here would then be: in any case of age, does gender ever matter?

Note 1: Also, hopefully this isn't an issue, but I hope we can assume for simplicity that 'kun' is used only for males and 'chan' is used only for females, **even though of course I know it's not true.** If not, then please explain why this assumption must be violated to really answer this.

Note 2: **My issue is the 'upgrading'** of last name-san to either 1st name-san or last name-whatever honorific, NOT why sometimes males/females can be called, resp, chan/kun. And also the honorific in 'last name-whatever honorific' is meant to be **fixed/predetermined** like as follows:

- Case 1: Bidatz Mikoto is female. Then Ashanti would say either 'Bidatz-san' or 'Mikoto-chan'. **Here, it's given** that 'Mikoto-kun' isn't a choice. Also, Bidatz-kun and any other forms of address other are somehow ruled out. How relevant is the gender of Bidatz or Ashanti in Ashanti's decision between 'Bidatz-san' and 'Mikoto-chan' ?

- Case 2: Bidatz Mikoto is male. Then Ashanti would say either 'Bidatz-san' or 'Mikoto-kun'. **Here, it's given** that 'Mikoto-chan' isn't a choice. Also, Bidatz-chan and any other forms of address are somehow ruled out. How relevant is the gender of Bidatz or Ashanti in Ashanti's decision between 'Bidatz-san' and 'Mikoto-kun' ?

- Or idk is 'any other forms of address are somehow ruled out' a huge or weird assumption to make?

  [1]: https://anime.stackexchange.com/questions/36915/why-does-naegi-call-togami-kun-and-aoi-san/40442#comment78780_40442
  [2]: https://anime.stackexchange.com/questions/66995/why-does-chika-call-miyuki-as-kun-chan-but-kaguya-san