This is how he survives the seemingly endless mares irl

"They accidentally Rock Lee'd him"--alternative artist's commentary

So this is Mahoraga's master, huh.

Based on the actual Kitasan Black's post-retirement life, no less. And yes, aghast, they did pretty much accidentally Rock Lee a retired racehorse.

Personally, I'm still waiting for fanart of Kitasan as a gym trainer or such (also based on the actual Kitasan's post-retirement life):

Nakayama-San said in twitter #1954496282871149031:

Kitasan keeps inviting the horse next to him to do endless running, so the horse next to him ends up losing weight.
So they started putting overwight [sic] horses in the pasture next to him to make them lose weight.
Once they slim down, they swap them out with another overweight horse.

Alanis, killed by overexercising