Lin's friend, Airi, is being stalked. The three brothers immediately come to her aid, saying they'll take care of the stalker. They sneakily follow Airi around and soon find out it's not just a stalker that follows Airi around...
I thought my heart was going 
to jump out of my chest.
Creí que mi corazón se 
me saldría del pecho.
Creía que mi corazón se 
me saldría del pecho.
Pensei que meu coração fosse
 saltar do meu peito.