Xu Zong accidentally traveled to Tresen Academy, became Spica’s trainer, and activated the diary system.As long as he writes a horse training diary every day, he can get rewards, but Xu Zong did not expect that his diary would be seen by horse racing girls such as Te Bie Zhou, Narita Road, Zhuo Fu, Dong Hai Di Wang, Beibu Xuan Ju… etc.Mejiro McQueen: “Wait, the fat colt in the diary isn’t talking about me, right? How am I fat?”Emperor of the East Sea: “Why does everyone know that I like to drink honey?”Narita Road: “Who is the crybaby? I…even if I win, I definitely won’t cry, probably!”Excellent qualities: “Why do you say I’m a bronze medal collector? Woohoo, trainer, you’re so mean.”Northern Xuanju: “What’s the assist card? Be careful of the hammer? Who is the hammer?”Satomi Hikari: “Huh? Why do you all call me Brother Zuan?”Te Bie Zhou: “Who is Te Bie Dai? Wait, do I have a sister?”Airihaku: “Is Shima an isotope from a parallel world?”Xu Zong’s diary is full of strange things, and the horse racing girls are all looking forward to it. As the content becomes more and more, the horse racing girls learn about the isotopes in the parallel world.