Armin carried himself differently when he was angry. Eren had known him for so long, it was easy to see the little things — the stiff posture, the piercing gaze, the way he didn't so much smile as he did bare his teeth.
Armin held Eren's chin between his thumb and forefinger, touch light.
"Eren," Armin said, voice low and soft. "Were you wearing my bunny dress?"
Eren swallowed hard. He wanted to focus his eyes somewhere, anywhere else, anywhere other than Armin's eyes — but he couldn't break his hypnotic gaze.
"M-maybe," Eren mumbled, haltingly.
He had. He had, and was, even knowing Armin would be upset, even knowing that he'd snap the stitches and stretch the hose and scuff up the heels. It wasn't Eren's intention to ruin Armin's few lovely things, but fuck, the thought that it could end like this wedged in Eren's brain and stuck there like a splinter.
Armin hmmed thoughtfully, rising to his feet and leaving Eren on his knees. He teased the hemline of the dress up with his toe until he could rub at Eren's stocking-clad package with the ball of his foot. Eren hissed through his teeth at the feel of it, tears stinging the corners of his eyes.
"Well," Armin said, magnanimously. "I suppose I should make you enjoy every last minute of it."