"It's important to start the race well, and I was there with her right from the beginning."
- Im Nayeon
 

"I beg to differ. I think how you end the race is more important.
And unlike you who had left, I'll be at the finish line waiting for her."
- Hirai MoMo
 

"Well, there's a problem then because... who said I ever left?"
- Im Nayeon

-

Kim Dahyun has a talent in running. She loves to run. In fact, she is the fastest runner on the track team. But Kim Dahyun also has a weakness; she is anaemic. She tends to faint often... especially when she forgets to (or delibrately not) take her medication. 

Im Nayeon was just a studious girl who lived in the same neighborhood as Dahyun, 

and Hirai MoMo was just a mischievous senior Dahyun had wanted nothing to do with. 

They were two extremely different people but they both had something in common; they both happened to have saved Dahyun's life when she passed out on the street. 

What happens when Kim Dahyun begins to fall for her benefactor? 

And what happens when she eventually get's her heart broken?

Will the other one try to mend it? 

...

It's important to start a race well... but how will Kim Dahyun end it?