Why setting up the background such as she was a ex-hero and still has the memory just to throw it outta window? MC went through a first few chapters to explain some concepts from the previous life then just goes on to ignore all his life experience. IDC about mind and being a child or something, the author made that she has the memory and is capable of thinking like an adult right in chapter 1 and yet a hero would make so many rookie mistakes. I'm going to drop this manga because of the inconsistency, the author needs to get it right, she can think like an adult or a child, it's one or another not both.