Princess Luna has been in touch with the moon for her entire life, and her little thousand year jaunt to actually live on it only deepened her connection. She is one with the lunar cycles, linked to Equestria's moon on an entirely enveloping level; psychological, spiritual, emotional, and even physical in ways that nobody else truly understands.

Yeah, screw the hype. It's horny Luna on her period.
Commissioned by anonymous. I don't get paid enough for this.