I'm a girl. I love horses. Isn't that all that's necessary? I remember someone saying girls have three stages in life: dolls, horses and boys. Some of us -- most fantasy writers I suspect -- got somehow stuck on number two.
What I love about horses: their nobility, whiskery lips, muscles beneath their skins, sad but intelligent eyes, the way they lip you, smell of hay breath, nickers, how they rub their heads on you after a ride to scratch their heads, smell of leather tack, thick manes, personalities, kindness -- oh, the list could go on and on.
I've fallen in love with a horse, but never owned one. In Year 10, we had to keep a diary and I kept a diary of a horse. Years later I saw my Year 10 English teacher, and she remembered me from that diary. My main character now owns that horse -- a sixteen hand skewbald called Big Patch (or Patch in the novel). But horses are definitely one of the appeals of fantasy for me -- both as a reader and writer. You won't see my characters on the quests on feet or on any kind of otherworldly beasts. Has to be a horse.