Mayumi's disappearance didn't last.
While the very paranoid trio was on their way back to the Gryffindor's tower, they found the redheaded girl sitting alone in the hallway, looking grumpy as hell and reeking of alcohol.
"Mayumi." Hermione, having recovered from her overdose of conspirasizing, stared. "Are you... drunk?"
Mayumi gave her a very unimpressed look, raised the bottle of sake in her hand, hiccupped, and promptly rid their ears of their last bits of innocence.
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