I am Just An Ordinary Girl

Kim Dasom, a girl with a weird hobby, which is, to be just an ordinary girl, means, she doesn't want her friends know that she is actually from a noble family.
And at the same time, she is one of the racers from street five or the other called 'S5'. S5 is a group,which consists of 5 racers with very expensive cars and also they have different capabilities in organizing an engine of car.
Park Chanyeol, a quite person, but happy-go-lucky . That means, he always smiles and is being childish when he with someone he's close with.Unknown background. He will try his best to get something he wants. Sometimes he can be a nerd, sometimes he can be naughty, and the other time he's gonna be matured. You will never know.
How can these 2 persons fall in love with each other?