100 years ago, titans suddenly appeared on Earth. Soon, human civilization veered on collapse due to the titans. Humans then built a giant wall to defend themselves. Within the giant walls, humans lived in peace, but, 100 years later, the giant wall is broken.
Eun-Jin (Gang Ye-Won) has failed in love 6 times. She struggles now to find her seventh love. Hyeon-Suk (Song Sae-Byeok), who is not interested in love or marriage, is her seventh love. Considering that her seventh love is her last, she tries her best.
Description: A detective story that evolves around two high school students, Kana Mizuhara, a curious girl who can't help looking after others, and her new classmate, Sou Toma, who graduated from an elite U.S. college at the age of 15. The two try to solve mysteries with a help of Kana's father who is an investigator..