In which Karkat Vantas is a surly ex-Marine who is absolutely for sure NOT a gray space alien, nor has he ever been a gray space alien at any point in his life ever, regardless of what this weirdo Sollux Captor claims when they meet in a bar one miserable Friday night. (i dont own this its owned by tumblr user jumpingjacktrash also known as jumpingjackflash on AO3. ok? ok great.)

There exists a disease in which a child is born with only half a functioning heart. The right side may work on its own for a time, but a heart cannot beat without its other half. But with care the other side of the heart can be guided toward life.