How Long Does It Take to Watch OneRoom?

Having just moved into a new apartment building, Yui Hanasaka makes a customary visit to greet her neighbor. When she learns that he is an upperclassman at the university she aspires to attend, she asks for his help to pass her entrance exams. Meanwhile, Natsuki Momohara decides to visit her older brother, who lives alone in an apartment in Tokyo. Elsewhere, aspiring singer Moka Aoshima reunites with her childhood friend, who is a hopeful novelist.

Three stories, although seemingly unrelated, contain the same essence: strings of fate will bind together those who share the same destiny, and one needs to look no further than a single apartment room.