"Today, I'll confess to Ko-chan!" A voice suddenly heard by Kouta Nitake, a high school boy who is not particularly popular. It was the voice of Ayano Yumemigasaki, a childhood friend who always has an attitude that doesn't look like him! Kouta didn't know that Ayano fell in love with him. "I really wanted Kou-chan to talk to me..." Kouta begins to be aware of Ayano's unrequited love. However, an unexpected side effect of "voice of the heart"...!?