Lee Taeyeon employs the service of "Heart's Tuner", a courier of sorts that delivers serenades conveniently right at your doorstep. She has been trying to capture Choi Minho's attention for years now and has come up with this plan as her last resort. Hopefully, this will help encourage him to confess his (non-existent) feelings for her. Unbeknownst to her, she only ended up introducing Minho to the owner of the company, Lee Jinki, who in turn allows Minho to come to terms with his heart's true desire.