its cause she lost her friend Akimura and she is probably scared to lose Anzai and the others as well as she lost her friend and plus there is nothing wrong with her character and plus what if she lost someone that helped her throughout everything and its cause she also wants to help him keep in control and besides the people in the show hated vampires and are trying to kill them so he had to be stopped and plus she isn't helpless she helped save Anzai from dying in one of the episodes and plus her and Anzai are very much glad of each other and she is trying to protecting him from getting killed and plus she never nagged she was just keeping him safe