The Green Thunder of Kuoh (Mr. L! Female Reader x DXD)

A story where Kuoh is defended by a woman who originates from the shadow of society, more people know her than you might think. Her name? Well she usually goes by Mr. L because she goes out disguised as a guy, but when she is at school he goes by Y/N L/N, a human who has knowledge of her sacred gear and the supernatural world, not only does she have her sacred gear, she learned the Thunder Brand technique, but why? Why does she do this? She does it to prevent others from losing what she has lost, family, however she despises the supernatural and believes that humanity should rely on themselves, but she works best alone, relying on no-one, especially the Supernatural, will she achieve her goal?