Drug Store in Another World: The Slow Life of a Cheat Pharmacist - Season 1 Episode 10 Power Potion / RK Gene Fluid
Overview: Vivi asks Reiji to make her a medicine that will make her stronger, but he responds that she shouldn't rely on medicines to fix all her problems. Instead, they ask Captain Annabelle of the Red Cat Brigade to help her train. Noela and Mina join their training session... but for some reason Reiji gets dragged into it as well, and he is forced to do jogging and strength training! Reiji immediately becomes exhausted and promises to make a medicine to promote muscle growth out of desperation.