The show starts with Kinji entering some sort of apartment building that isn't his to meet Aria in secret. He comes inside when all of a suddenly Aria started sexually assaulting him which triggered his Hysteria-Mode to awaken. With his special ability in effect, he concluded that the person with him isn't Aria but Riko instead. He concluded this after feeling her breast in which Aria have none.
|"Just so you know, I hate harem routes!"|
|"I'm not really a Butei Killer if I haven't killed anyone, right?"|
At first, both Kinji and Aria hesitated but soon agreed to help Riko out since stealing from criminals isn't a crime not to mention that they are only helping to take back something she initially owns. And so, the three had a deal.
The next day, Riko goes to school in her gothic lolita uniform and dazzles everyone with her beautiful smile. She flirts with Kinji during school hours and managed to put him in trouble too during the exam. Apparently, she's doing this so Kinji would learn to trigger Hysteria-Mode ON and OFF at will.
The two walks home in the rain under one umbrella and acts like a couple. Shirayuki interferes and tells her to butt out as Kinji already kissed her. Riko counters this argument by saying that Kinji and her have already hit second base. This caused Shirayuki to be in a state of shock. The shock didn't take long though, as anger builds up inside of her.
|"I won't let you steal my Kin-chan, you thieving cat!"|
|Riko as the wolf.|
|Aria as the demon.|
|Shirayuki as the ghost.|
|"Please don't stare too much, it's embarrassing."|
A new day starts and we see Aria and Kinji sneaking together into an unfamiliar building. Apparently, Riko asked them to meet her at the location but they couldn't trust her words and braces for battle instead.
|"Are you ready?"|
|"Freeze and put your hands up!"|
|"Welcome back, Master"|
10th Ammo: Special Training
|"Come back soon, okay?"|