Jun decides to help Shiena with her studies, which drives Naori crazy. Rumi, on the other hand, seems unusually indifferent about it. However, for Naori, it's clear that she needs to keep an eye on them. So, she quickly invites herself along.
Besides, Shiena's the one 
who suggested it, right?
علاوةً على ذلك، شيينا هي من اقترحت الأمر، أليس كذلك؟
Además, te lo propuso ella, ¿no?
Además, lo ha propuesto ella, ¿no?
C’est Shiena qui t’a proposé.
Inoltre, te l'ha chiesto Shiena, no?
Além disso, foi a Shiena
que sugeriu, não foi?
И вообще… это же Сиэна предложила.