Will It Be the World or Her?(2017)

Sekai ka Kanojo ka Erabenai

Even though Kouki Nakagawa and his childhood friend Ayumi Fujisaki bicker like cats and dogs, one thing's for sure...he's head-over-heels in love with her. But when he finally starts to confess his feelings, his awkward-but-nice-enough classmate, Jindou-san, announces that she's Kouki's girlfriend! She tells Kouki that he can never tell Ayumi his true feelings...because if he does, the world will end in apocalypic disaster? What's a guy to do?

(Source: Kodansha USA)

Note: Includes 5 extra chapters.