Eren is on-edge from the moment he suddenly finds himself in the room. It's different from the way it was described before, but even so it's not hard to figure out what's happening. A quick attempt to contact his friends over the Network confirms it. Bristling, he spends a moment taking in the room. The roses are ignored, and he remains standing rather than try to sit on the weird cushions. The drink also goes ignored, since he doesn't trust his 'hosts' enough to eat or drink anything directly provided by them.

His scowl deepens with barely contained anger as he folds his arms and begins yelling at the seemingly-empty room.

"I know you're here! Show yourself!"