I love the headcanon that once back on Erid, Rocky refuses to give up the astrophage solution until his starving dying alien friend is safe.
It's even funnier to think that he never told Grace about this.
Grace, recording a video diary for future human visitors or something:
"Oh boy, and the ERIDIANS are some of the nicest people you'll ever meet! They've done so much for me, I can't even put into words how grateful I am! Once we arrived on Erid, their top priority was saving my life despite the fact that their planet was dying! Me, a stranger, someone who doesn't even belong here! They went above and beyond for me, and all just because they're SUCH amazing, caring people. Right, Rock?"
Rocky, having flashbacks to the time he yelled "STAY THE FUCK BACK, NO YOU CAN'T HAVE THE TAUMOEBA! WHAT DID YOU JUST SAY? ALIEN ISN'T PRIORITY? FUCK YOU! ROCKY WILL KEEP TAUMOEBA FOR HIMSELF! ROCKY WILL BLOW UP ALL OF ERID! ROCKY WILL....":