Eponine lets go of the muzzle in alarm as they stylist begins to scold her, but she steps closer, hissing,

"He cannot BREATHE, Madame. You cannot make him wear something that will kill him. Your clothes are silly if he cannot breathe."

She immediately goes to undo the muzzle again. Unlike the stylist, Eponine has completely forgotten about the cameras possibly watching her and she wouldn't particularly care anyway. This man was almost a stranger to her, but he was Howard's friend, and that was enough. She'd help him if she could.