As a stablegirl it's your duty to look after the horses at the horse riding academy and care for their every need. As the deputy to the head stablegirl, you have a lot of responsibility.
For starters, you have to make sure that each horse is fed, groomed an mucked out. You don't have to do each one yourself, because there are others. You just have to make sure that they do their share of the work and cover for them if they're absent.
Today was different though. Today it was the head stablegirl who was absent due to an illness. Which meant that it was up to you to look after the academy's prize stallion, Zephyr.
Entering his stall, you inspect Zephyr's white glossy coat. It's clear that the head stablegirl is passionate about her job caring for Zephyr. All the stallion's needs are seen to.
Just as you finish filling Zephyr's hay net and start mucking out his stall, the prize stallion starts to nuzzle against you, rubbing his nose against your back and down to your butt.
Chuckling to yourself, you turn towards Zephyr to give him some attention and affection. It's then that you notice that the stallion's arousal.