Everyone needs to calm down. Amamiya's not drugged, that pic is of her and Shiragiku on a train (you can see the seats and part of the window) and she's just sleeping. She's riding a train with Shiragiku because he said he'd take her to the prison. The whole point with Shiragiku is that he thinks he's hot shit now that he's gotten laid, but is really still the insecure whiny bitch he always was. The whole point of Kurumi is that he's overly excitable and lets his emotions and worst impulses pull him to bad conclusions, then has to learn from his mistakes to control himself.
No NTR is going to happen. I wouldn't be surprised if Shiragiku tries something on Amamiya and she beats the shit out of him.