Mukai Naoya is in a relationship with Saki Saki, but another girl, Mizuse Nagisa, asks him out. He makes the unthinkable decision of asking them if they would be up for both dating him at the same time.
One guy for one girl!
!فتى واحد لفتاة واحدة
Ein Mädchen für einen Jungen!
So läuft das normalerweise!
¡Un chico para cada chica!
¡Un chico para cada chica!
Un couple, c’est deux personnes !
C’est du bon sens !
Un ragazzo, una ragazza!
Um cara pra cada garota!
Разве не очевидно? Пара — это 
один мальчик, одна девочка!