Rosy unexpected strenght challenge VS the weak postman

Description: Rosy, a black belt and expert karateka, is training at home for an upcoming competition when she's suddenly interrupted by the postman's arrival with a registered letter to sign. seeing her, the postman is surprised and intrigued by what she's doing, but also quite perplexed and doubtful about rosy's true abilities and, above all, her true strength, considering she's a woman, despite her vast experience. what better opportunity for her to get in some extra training and dispel any doubts our dear postman has? let the strength challenge begin!