Crazy Dog Plus Three

In a Western fantasy world with magic. Jia San didn't believe in love, much less in eternal devotion, so he bound his mount with a contract and set a time limit. The Emperor's magical research went awry (he messed up), turning his true form into a monster. Who would have thought some idiot would forcibly contract his true form as a mount? How could he tolerate this? He had to teach him a lesson in every way possible! Jia San: Who is this foolish Emperor, and why does he keep causing trouble for no reason? And how does he know so much about my affairs?