That cow would be Luna, the friendly bovine Mayer has trained into the riding companion of her dreams, according to The Associated Press.
"She thinks she's a horse," Mayer told the AP from her family's farm in Laufen, Germany, a few miles from the Austrian border.
Luna wasn't ready for cow-back riding right away, however. The transformation from stubborn farm animal to long rides in the German countryside was nearly a two-year process, gradually progressing from strolls through the woods to Mayer finally mounting her trusty steed.
At first, "she was really well behaved and walked normally," Mayer said. "But after a couple of meters, she wanted me to get off. You could see that she got a bit peeved."
Luna can't quite jump over the moon, but she does know a few tricks. Mayer has Luna hopping over makeshift hurdles of logs and beer crates, and even socializing with other horses.
Cows, on the other hand, are a different story.
"Cows don't really like her ... they're jealous because she always gets goodies," Mayer told The Telegraph.
What do the neighbors think of the town cow-girl?
Martin Putzhammer, 17, was curious at first, but he's since warmed up to the idea.
"At first I thought it was kind of weird -- a kid on a cow?" he told the AP. "Had to get used to it, but once I did I thought it was pretty funny."
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