Ruka is hellbent on knowing the full story behind Kazuya and Chizuru's relationship, and once she does she decides to take action.
She's a rental girlfriend, you know! 
You two don't have a future together!
!إنّها حبيبة مُستأجرة، لا مستقبل لكما
Sie ist eine Mietfreundin, checkst du’s eigentlich?
Ihr habt keine Zukunft zusammen!
Lei è una ragazza a noleggio!
Ela é uma namorada de aluguel, sabia?
Vocês não têm um futuro juntos!
Не забывай, она девушка напрокат.