IU and Thunder are best friend. They help each other in lesson as they lost their parent. IU was a girl who has in love with Thunder. As they are the best friend they might have some relationship to each other. Thunder's sister Sandara Park doesn't like beening friend with IU as she is very propular actress and IU is poor. As you know rich people don't like staying with poor people. Dong Ho is the one who kidnap by the man and buy by IU. IU was in love with Thunder since they are in High School. But in December hoilday Thunder has a very bad car accident. Thunder takes 1 week to wake up. When he wakes up he remember everythings expect IU(his best friend). Since IU hears that news, she was very sad........