Thinking of Grace and Rocky getting so bored on the way to Erid and also them just being so sad they they can’t speak each others language, no matter how much they understand it’s just not physically possible. But maybe just maybe there’s some word in their respective languages that they can sort of say (not very well) but enough that someone would understand it. And they spend days going through everything thats sort of similar to the vocal range of the other.
POV Adrian when they finally get Erid. Your mate is back with this freaky alien that speaks in such a condensed range of tones and you understand nothing it says but it seems happy to be here and happy to meet you. And then in the middle of a ramble of incompressible sounds it says, in the strangest accent, “thermometer” and then goes back to utter nonsense.
Rocky would absolutely be capable of learning musical notation and "singing" earth music (the instrumental melody--not the lyrics).
From his perspective Rocky is just reciting absolute gibberish, but for Grace your alien friend just bursting out into recognizable earth music would probably be endlessly amusing.
Also imagine in the future some astronaut-diplomats making second contact with a group of Eridians and just..... getting Rick-rolled.
