Oh, Those Hanazono Twins Vol. 4 (Kodansha, 2022)

Between being busy as the all-in manager of Ranko's school band and having a study session with Yuriko, the average high schooler Tatara Tani wouldn't think of fooling the whole school with his ongoing fake relationship with Ranko. When the summer break starts, Ranko and the gang's motivation to practice becomes even more extensive as the school festival becomes closer, and Tatara tries to find ways to help the band in his own way. All that while juggling a top-secret trip with Yuriko and gourmand dates with Ranko?! The twins are going on the offensive this summer!