Might I hear some of your miscellaneous Spectre headcannons?
no worries, these are my bread and butter headcanons that I just kinda default to adding to his background radiation:
My biggest, most important favouritest Spectre headcanon: legally speaking, he is dead. The orphanage pronounced him dead twice actually and even the Hanoi Project staff were like, "dude, what the fuck" but that lightened their work load since they didn't have to run interference on his disappearance unlike with the other kids. BTW this is partially why he doesn't wear a mask or change up his avatar too drastically, he thinks he doesn't have to because his civilian identity is considered dead my misadventure, body not found.
This is in a grey area between "canon" and "headcanon" but I do think Duel Links has canonised him being a psychic duelist insofar as understanding the language of his monsters and actual real life trees (he's just like Jasmine Deltora Quest)
He was born with congenital bell's palsy and that's partially why his face is like that as well as tics. These were exacerbated by the Lost Incident and Ryoken stresses about this but its fine, he promises these were there prior
On the topic of the Lost Incident, he did cry and miss his mommy more than he lets on but no one could have predicted that his mother whom he so sorely missed was a Literal Tree
He has three birthdays (the day he was actually born which is unknown, the day that the orphanage found him, and the day ryoken found him) but he celebrates none of them
He dresses so well as an adult because he wants to take full advantage of the Kogami money lolll because he only ever had handmedowns prior, it makes him feel more like a Respected Person if he can choose what he wears and is their first owner (but I saw art of him wearing Ryoken's handmedowns on twitter and that's soooo cute so I will permit that haha)
He taught Ryoken how to climb trees
He was homeschooled by the assistants/Lieutenants and kept out of public schooling so he does have an almost university level grasp of a few different disciplines but they kind of free schooled him and just let him learn what he wanted to learn which was biology and language in addition to their specialties
He has a very special bond with Aso in particular because they have a shared love of reading. His bond with Kyoko is a bit more fraught because I know he was inventing brand new misogyny against her as a kid because oh boy does he have complicated feelings about red headed women in positions of power and authority over him (the lady who found him was also a red haired woman and that makes me insane). Dr. Genome is cool to him but they have the "we're a bit too similar so we get on each other's nerves" problem. And I do think he was bit of a brat to them as a kid because they served him up a gold plated ticket to getting out of trouble to be fair but he loved them so much!! Please keep letting me be your guinea pig!!!
Not so much a headcanon as a random symbolic connection, I do associate him heavily with the tarot card The Moon