For both, their entire world was swallowed by the sea. One metaphorically... one not so much.
Damn this was sad. Teenagers just have no idea what to do in those kind of situations (hell most adults don't), so Yuna clung onto the only two things that gave her happiness. Koma, and the end of the world. I like how so little is actually shown, because it really helps us by putting us in Koma's shoes by feeling helpless and most bullying is psychological so seeing anything would'nt super help.
Great story, never reading it again. Imma go find fluff