After a fight Hayate, Nagi heads to the apartment complex to hang out.  But her “little sister” is the only one home.  This might be Nagi’s chance to find out what Ruri’s real goal is. 
Your reason for getting close to me.
El motivo por el que quieres acercarte a mí.
La razón por la que insistes en estar cerca de mí.
O que você quer se
 aproximando de mim?