Tune in to the midnight heart. 1 finding the girl behind the voice

At the end of a difficult day, the haughty but purehearted rich kid Arisu found his only solace in the voice of another girl his age, who hosted a livestream under the pseudonym "Apollo." Then, one day, the broadcasts stopped. Arisu has dedicated the years since then to finding Apollo's true identity, and he's narrowed it down to one particular high school. He transfers in as a student and figures it'll be a cinch--but then discovers it could be...