My favourite Adrian headcanon is that they're a biologist/zoologist who has seen so much shit, they're completely unphased by any and every alien habit of Grace's.
I mean full-on khaki-shorts-wearing, traversing-wilderness-with-nothin'-but-a-machete Adrian who yoinks snakes outta trees and pets swamp puppies and will unflinchingly dig around in elephant faeces for signs of a rare parasitic tapeworm if needed.
Oh, humans eat socially? No problem, Adrian has observed many many animals eat. Did you know that an obscure species of small underground dirt creature from the north side of Erid also eats socially? Adrian can give you a not-so-short presentation on them.
Oh, the human has no external carapace and so its internal sounds are absurdly loud, wet and off-putting? No problem, Adrian was just conducting an expedition last month researching the incredible eridian animal, the Wet Loud Worm from the south-east region of Wet Loud Wormland. They're desensitised, it's fine.
Oh, Grace leaks often from many orifices and it can be a bit of a learning curve to get used to? No problem for Adrian, see Wet Loud Worm paragraph again!
Meanwhile, Rocky is bewildered as to how he's managed to third-wheel both of his relationships, because both Adrian and Grace are nerds who nerd out about things, and Adrian is shaking in their carapace with enthusiasm to learn more about human culture and biology, not to mention everything about earth animals. And yeah, sure, Grace might be a molecular biologist, but he'll be damned if he'll pass up an opportunity to learn about alien fauna from a fellow scientist, and yes, Adrian, he'd love to hear about the small underground dirt creature from the north side of Erid, and he's so excited to learn more about the Wet Loud Worm, do go on.
