Tearmoon Empire: Volume 13 by Nozomu Mochitsuki

Two months after the introduction of the SEEC program at Saint-Noel Academy, it’s finally summer break. And Mia isn’t returning to the Tearmoon Empire alone! She’s got Patty with her, plus Bel, Yanna, Kiryl, and of course...her personal bodyguard, Abel! But even summer break is not time off for Mia. Except it’s not the quickly approaching famine taking up her time, but Ruby’s impending engagement to Hildebrandt, Mia’s horse-loving cousin! Since Ruby’s heart belongs to Vanos and Mia a sucker for high-stakes romance, Mia contrives to break off this engagement and match Ruby with her true love. How does she plan to do this? With a horsemanship tournament!...

Wait, a what now?