Jongin's a man who wears his heart on his sleeve, so it just makes sense that he'd end up wielding the interdimensional Heart wand as a guardian of the sun. And by what seems like fate, he ends up meeting another guardian named Kyungsoo who has the brightest heart-shaped smile and a way of making his heart flutter.

The classic story of how first impressions can actually be wrong sometimes.

Jongin and Kyungsoo are just best friends whose mutual friends think that they're together. For some reason, Kyungsoo wants to mess with them and so asks Jongin if he'd like to be his fake boyfriend for a day. And Jongin, being the lovesick man that he is, agrees to it.

A quick race at the start leads to a slow race for the heart. It's the day of the big relay race and Jongin's finally found what he thinks is the perfect time to confess his feelings to Kyungsoo.