Exhibit A. Emi-chan admits that she used Kira’s name for her Starbucks cup.
Exhibit B. She tried to say it couldn’t have been her’s, but look closely at the time the message was sent and the time on the cup. Thank you, @better-holmes-and-deductions for pointing it out.
Exhibit C. She stated it wasn’t her’s, but said cup is in the picture. As well, I knew Emi-chan loved coffee, so the possibility that she ordered said coffee is very high. Suspicions were cleared with this image.
Emi-chan is Kira.