20th Century Girl

Synopsis:

While Yeon-du is abroad in the US for heart surgery, Bora, her best friend, is tasked with gathering all the information she can about Baek Hyun-jin.
Pung Woon-ho, Baek’s closest buddy, is who Bora chooses to get close to initially.
Bora’s poor scheme, meanwhile, takes an unexpected turn.
A year before the turn of the century, in 1999, Bora, who turns seventeen, experiences first-love fever.