Yixing's banal life routine is shaken, literally, by a 7.0 quake and the resulting aftermath. But great big waves and collapsed buildings aren't the only things disaster brings to this coastal town. While assisting with the oil spill relief efforts, Yixing and his friends find a strange girl caught in the muck and debris, and they soon discover that the've rescued a namelss mermaid with some trouble of her own. "Jinyu" has but a

Jongin's decision to take the next big step in his new relationship doesn't goes as planned. Sohwan seems to be the only girl who doesn't want to hear "I love you." 

A slip of the tongue launches Jongin and Haru into the next stage of their friendship.

Yixing and Yin met as children. He was a bullied little boy longing for a friend and she, a lost, abandoned imaginary princess in search of a new home. But Yixing is growing up, and his imaginary friend is worried that he no longer believes in her. It doesn't help Yin that she's also fallen in love with him.

Jongin's girlfriend ponders the difference between statues and men. 

Mijoo struggles with her hidden feelings for Yixing, but when she can't afford any distractions during finals week, there seems to be only one, dreaded solution.

When the usual security guard gets promoted, Se Rim ends up asking the new guy to walk her to her car when it gets too dark. On the way, Jongin teaches her a thing or two about overcoming fear and finding the light in the darkness.

When Chanyeol discovers an indiscreet package in the mailroom, he confronts his girlfriend about how her underwear ended up in the postal service.