Krystal Jung could only be a figment of his imagination. Hers is a name that comes to life in journal entries he managed to find in his apartment. Being someone without his own memories, he relies on the day-by-day narration of Krystal Jung about who he is and who he's supposed to love. It's been years since her last entry, and a year since the accident that took more from him than just his memories. 

Can he still find the person that signs "Yours Truly, Krystal Jung"? 

   Kim Jongin is a man tormented by a past he can't recall for himself. Living the good life, having a stable job, being a bachelor in the midst of Gangnam: Kim Jongin is a self-made man. However, despite his achievements, a gaping void resides in his heart.

Can he continue his search even if he isn't really whole?

   Im Yoona is--what the . Who the does not know Im Yoona? The center of SNSD, a popular all-girl group in Korea. The goddess every single man has a crush on. Fame, fortune, great looks. She has it all--including the apartment complex right next to Kim Jongin's. By a of luck and a bottle or two of alcohol, she finds herself inside his home and into his life.

Can she play fairy godmother and get the two lovebirds back together?

Or will she fall for her pessimistic neighbor's charm?