To Luna, the Tantabus was a self-imposed penance. If the ponies around her refused to acknowledge the true depth of her guilt, then she herself would see that she was punished for all she had done, fully and to the last. The Tantabus was the long shadow of her own past darkness.

It never crossed her mind for an instant that it might have ambitions of its own.

Contains: oral sex, regular sex, magical futa, verbal abuse, possession, bad end, not a lot of plot.

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Art cropped from 'Royal Peek', found on Derpibooru, by Cuddlesong and King-Kakapo