The Girl I Saved on the Train Turned Out to Be My Childhood Friend, Vol. 1 (light novel)

While on his way to school one morning high school second year Ryo Takamori saves
his childhood friend Hina Fushimi from a sexual harasser on a crowded train. Although
the two are practically opposites in appearance and popularity, not to mention the fact
they haven't spoken since middle school, Hina finds herself smitten with the oblivious
Ryo. A frustratingly sweet, zero stress romantic comedy!