Park Yu Me , a half Korean,Chinese and Japanese girl , has a lot to look forward to. Her dreamy boyfriend , Byun Baek Hyun , will soon be home from Football camp , where he's spent the entire summer. Yu Me also has an idea for a new project that challenges her to dream big. While Yume is perfecting her plan and counting down the days until Baekhyun return , life throws her a few things she didn't expect - some exciting , some scary . 

Krystal and Sulli is leaving Yume out , as usual , but when Krystal delivers some shocking news, Yume will need to decide what kind of friend to be. There's something going on with Yume's brother , Chanyeol ,that he doesn't want to talk about , and Baekhyun is acting secretive on the phone. There's also a cute boy named Kim Yugyeom who likes Yume .... a lot, and yume thinks she might like him too. With a wedding to plan , friends and boys to worry about, and a project that keeps calling her name ,  Yume wonders what's in store for last of summer , because at the end of the days , she is a girl who always, always , always listen to her heart.