[quote=@AngelofOctober]
[@Stern Algorithm]

"Cripes!" Kyouran called out as Akane suddenly threw his glass on the ground. "I don't know who this 'Suna-kun' is, but if you need to beat someone up, you can rely on 'Big Sis'," Kyouran said, referring to herself.

^She does realize who she is inviting to call her Big Sis? Akane can be kind of Yandere about his relationships. This is going to get really out of hand now. I just felt a big bubble of excitement when he heard the word Big Sis now it's all he's going to call her and now he's going to ask her for instructions
[/quote]

The feeling I'm going for with Kyouran is that she's kind of a yankee (in the japanese sense) or Yakuza-esque, honor among thugs kind of deal. Her comrades are her family and she just wants to be chummy and build camaraderie. It would take a lot for Kyouran to notice that Akane is being yandere. This is also insurance, if he's happy when he's around her, then that's a positive feedback loop with regard to his power.