黑帮老大哥我的365天在Faustine, a romantic teenager, decides to spend her summer in the countryside with her grandparents. Upon her arrival she briefly meets a teenager named Joachim and quickly becomes obsessed with his family, spying on them from a distance.　　Eventually she begins to integrate herself in to their lives, befriending Joachim's cousins, flirting with Joachim himself and developing a crush on his uncle.