A human sized set of horse equipment.
"That's odd, did that girl leave this behind?" you ask yourself as you pick up the saddle. "...And why is it small enough to fit people?" Before you could wonder any more about the situation, you feel a sense of calmness as you hold the leather in your hand, as if it was something you've always wanted to hold since you could remember. After a while of feeling the leather, you look over the saddle,rubbing your hand across the seat and down to the hanging stirrups, then holding up the bridle, noting how clean and new it looks.
You thought about bringing the set along with you, in case it really did belong to the young rider, but it occurred to you that it was bulky enough to be a burden dragging it around. That's when a strange thought popped into your mind.
'Why don't you wear it instead?'
You chuckle at the idea of wearing something a horse would wear. It did make some sense to your logic, though. The equipment was clearly too small for a riding horse, but just the right size for someone like you to wear. And besides, it might humor the both of you to be walking around looking for a horse while wearing horse riding tack.
Though hesitant still, you begin to slip the saddle onto your back, buckling it into place. The position of the seat of the saddle and the stirrups remind you of piggyback horse rides as the seat was angled in such a way that allows the rider to be upright even when you were as well. Not wanting to be incomplete, you slip the bridle onto your face, allowing the bit to fit at the back of your mouth. The bit felt a little uncomfortable and had a sharp taste of metal, but you felt compelled to leave it on despite the inconvenience through a strange sense of loyalty.
After some struggling, you manage to get all the equipment in place, nice and snug on your body. You felt silly wearing something meant for horses but also a growing sense of pride as well. Deciding it was good for now, you continue your search for the girl's horse.