Eren’s plan had succeeded, by kidnapping you. You guys were in a cabin deep inside a forest outside of the walls. He had forced you into a onesie and tied your hands ‘gently’ together to stop any movement & escaping.

He held you tight in the bed that he himself made with his hands along with the house, just for you. The others are probably aware of your disappearance by now and are seething by now.

He held you in the quiet room, in the dark, and asked. “Are your hands hurting from the ties?” Not like he cared, he was just asking because he didn't want to hurt the precious skin that he worshiped.