Most teenage girls would probably react to a literal cavern of sweets with more than a flat expression and a certain wariness. Most teenage girls are not Homura.

She turned sharply when Superman came in, and despite the obvious clue of the outfit, she treated him with a faint wariness as well. She was somewhere she didn't understand, and the overabundance of sweets... had associations in her mind. There'd been a witch's barrier like that.

Still, her note was cautionary rather than accusative. "This has the semblance of a rather sweet trap."