(-Taiki "Yami" Himura is an OC made from Digimon ReArise, so these headcanon's will revolve around said game/series-)

Headcanon 1
Like i have stated in my art book, in which i introduced Yami
He doesn't like Taiyaki
Though mooncakes and Mayu's cookies catches his attention

Headcanon 2
Unlike the in-game Herissmon.
Yami's Herissmon is much more quiter and think about consequences, but he's still innocent (-idk how that works-) and child-like (-just traumatized- -)

Headcanon 3
Also going against what happens in the game. Herissmon digivolved shortly after the "The librarian, Datamon!" ARC
When Michi and Salamon eventually talked about going against enemies just to digivolve in "Salamon's Training Session"
Yami and Herissmon wanted to explain about that, but.... They went off to find Digital Points to fight lost Digimon's and Spirals...
Both of them went to follow them so they wont get hurt...

Headcanon 4
Dimensional Vortexes appear time to time, just like how it is in the game.
But if it were to be in an RP or Anime
Dimensional Vortexes appear in certain places and stay there until they close
And it opens in the same place too! So you dont have to run around to find them

Headcanon 5
Everyone calls Yami by Taiki, even after soo many times he insisted jist to be called Yami
Right now, he doesn't bother to correct them anymore since he's comfortable with them now

(-Alrighty! Thats all that i have right now since i only reached  the "Salamon's Training Session" ARC-)