Kakushitagari no Douki-kun

A muscle-loving woman meets a lean-fit guy! Look at them! Touch them! Love them?! A slapstick comedy all about muscles. Karen is an office worker who is obsessed with toned, muscular guys. But her muscle fantasies are always interrupted by her nagging coworker, Hosokawa. He's scrawny, nerdy, and totally not her type. In a bizarre chain of events, Hosokawa's secret is laid bare for her to see! He's built just like the muscle-crazed Karen fantasizes about every day, toned and muscular! Now, she wants to touch his body, and she makes a risqué proposition! (Source: MangaPlaza)