Though 97 can feel pain and eat and drink and other mortal things, he cannot actually die. While 69's parts will slowly rust and breakdown and have to be changed and repaired and eventually reach a point where adjustments to her form are no longer possible without damaging her personality, he will be there, the same. Except for one thing- slowly but surely, his memories will start to vanish. one day, he'll be a blank slate. All memories and fondness for 69 gone. Who really has it worse off?
OH MAN I REALLY LOVE THIS HEADCANON??? ?
I FEEL LIKE... THEY BOTH HAVE IT BAD,,, It's actually blog-canon that 69's mental state and sanity are compromised because of how much she damages and rebuilds herself, and over time she's losing morality and emotions -- it's like she's so obsessed with becoming "human" and making her "body" as realistic as possible that she's really losing her humanity. I guess it's like she's so obsessed with an outcome she's slowly forgetting her resolve?
So if 97 is immortal aside from his memories, someday he'll forget her entirely and vice-versa. She'd remember knowing him, and that he's important to her, but the actual memories of the time they'd spent together would be lost to her -- omFG WHAT IF SHE EVEN FORGOT HIS NAME??? LIKE SOMEDAY LIKE WAAAY LATER SHE'D GO UP TO HIM ALL FRIENDLY AND STUFF HOLDING OUT A HAND FOR A HIFIVE AND HE'D BE ALL "??? who are you" AND SHE'D BE LIKE "WHAAAT Y'KNOW ME! I'M... UH... I EVEN GAVE YA A NICKNAME! 'CALLED YA,,, UH,,, what was it again? Aw shiiit did I jus' imagine meetin' you? Naw, I totally 'emember ya... You're..."
AND HE WOULD BE LIKE "uh okay..." AND GO AWAY FROM HER BECAUSE SHE'S ANNOYING HIM AND SHE WOULD BE TROUBLED OVER IT FOR THE NEXT FEW MINUTES BEFORE SHE JUST DISREGARDS IT? BUT THE NEXT TIME THEY MEET SHE GOES THROUGH THE SAME THING AND 97 IS LIKE YOU ALREADY SAID ALL THIS AND 69 IS LIKE WHAT REALLY??