The Margrave's Daughter & the Enemy Prince manga volume 4 features story and art by An Ogura.

Having survived her visit to Eclipse Manor, Anna returns to school with plans for a power-grab! Anna and Claire recruit Erena — the latest victim of Iris's bullying — to join them in staging a play, in hopes that the performance will upturn the social hierarchy at the academy. If they can successfully disrupt the power dynamics at school, the kingdom's nobility might just follow suit…

As abruptly as he departed, Prince Kenneth returns from his mission with shocking news of the Eclipses' plot to seize power in Albion. In spite of these sinister revelations, Anna refuses to let Kenneth lose his nerve.