i just realised that grace changed up his shoelaces by the end of the movie AND MAY I JUST SUGGEST—
—i know there's a popular headcanon or it's natural to think that grace might've gotten some kind of tattoo on his arm (or taken his scar from rocky on his arm as a similar symbol) to symbolise the bond he has with rocky sometime into his life on erid.
may i suggest that sometime into his life on erid, adrian, of course, inevitably grows very fond of their mate's unlikely alien friend and the saviour of their entire species and everything that lives and everything that will live on erid.
and one day after rocky and adrian have had a Serious Discussion and decided that they very much hold grace with the same significance as of a mate, they inform grace that they would very much like to engrave something that represents him on their limbs with his blessing.
come the question of whether grace would like to partake in marking his skin too.
he would LOVE to, i'm sure, but maybe there are no pigments on erid that the engineers can certify to be 100% safe for alien skin and so maybe... maybe it wouldn't be a good idea to risk it. or maybe, grace knows he can't deal with a tattoo gun and suggests alternatives! or maybe, he goes aights sure let's do it but he passes out at the sight of the tattoo-gun-like-thing that the engineers manage to put together and everyone panics and he has no choice but to suggest alternatives!
ultimately, the interim solution (which ends up being permanent anyway) is to change up his shoelaces. they've seen him wear those beat up converse for so long it's essentially part of him anyways. one to represent rocky and one to represent adrian. rocky's on the right foot cause he's his rock, his right hand man, the platonic soulmate he'd give up his life to save. grace chooses the fabrics based on their traits too (e.g., the silvery one seems to have little grooves, kind of like metal wire - engineer???, and maybe the teal one is something like cotton???) (i can't clearly tell this from the screencaps but let me dream). grace explains the symbolisms in further detail, making things up along the way of course but finding it all oh so fitting and apt and true:
shoelaces that come in a pair to start, like how rocky and adrian have been mates for hundreds of years so far until he came along.
shoelaces that both need to be in place at all times for him to walk well, like how they're always going to be with him for as long as he lives on erid, and how grace has inextricably become dependent on them for joy and comfort and life.
as grace weaves the new threads into his shoes, he explains how it symbolises their paths crossing and the memories made along the way.
and as he goes on to tie the knot (!!!) he promises to love and care for them as they do for him for eternity.
rocky stops him, though. says that eternity is a long time, and that they don't need grace to promise them an eternity,
'for if you ever change your mind and want to go home.'
they bicker about it, of course.
grace doesn't knot them in the end, not because he wants to go back to earth. he no longer does, and hasn't entertained the thought in a long time. he just lets rocky win the arguments sometimes, and besides, he can work out some alternative symbolism in his own heart, can't he?
so if you see saviour grace walking around erid with his shoelaces untied, it's only because he doesn't need to knot them.
why would he, when he isn't going anywhere? why would he, when he no longer needs to dress for leaving, or for running away?
why would he, when he's already home?