How heavy are the dumbbells you lift?

 Hibiki enjoys the finer things in life, and when it comes to food, she's downright indulgent. When it becomes clear she's getting chubby, she decides to better herself by joining a gym. In her attempt to find a casual gym, she meets Akemi - a comrade-in-arms. Little does Hibiki know, Akemi has an ulterior motive. What will this wonderful world of fitness have in store for Hibiki?