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.
I can't think of a solution besides 
going out with both of you!
!لا أستطيع التفكير في حلّ آخر غير مواعدتكما معًا
… keine andere Lösung als
eine Dreiecksbeziehung einfällt!
Le ménage à trois !