Erwin doesn't particularly enjoy anyone paying attention to his stump, or acknowledging its presence. He doesn't mind Levi touching his gear scars, though, or the new callouses the prosthetic has left on his chest. Those scars, weirdly enough, feel earned, while the scars on his stump feel given. It's a strange distinction, but one that is very much there in his mind.

The muscle on his right shoulder used to bother Erwin too, when it had atrophied and gotten smaller than the muscle on his left arm. It's gotten stronger now, from moving the prosthetic, leaving him more or less symmetrical again, so he stays loose and relaxed while Levi touches it.

When Levi sits up, Erwin does too, taking his arm with a soft, murmured thanks. He's well practiced in getting it on now, holding the arm itself by pressing it against his body with his stump as he adjusts the straps, then holding the main strap in his teeth as he lifts the arm and slots it into place. He can do it himself, but he won't protest if Levi offers some help with the straps.

Once it's on and secure, Erwin flexes the hand a few times and moves the elbow up and down, making sure it's satisfactory, before putting both arms around Levi and lowering them back down to the bed.

"There. Much better."