幼なじみ彼女が浮気していると彼女の友達から聞いたのだが (Associated Names)

One day, Ibuki Takada is shown a photo on his girlfriend Mizuki Yuge’s smartphone by her friend Iida Maya. When he sees her walking with a smile and arm in arm with another man, he begins to wonder if she is cheating on him. Worried about what to do, Ibuki turns down Mizuki’s invitation to…