Mated To An Enemy - Chapter 457 Bound Together

One day I got a younger sister.Only I know her true identity.

A man with a lifelong martial arts background, raised in Asia due to his family's profession, moves to the US for education and work. He discovers Historical Medieval Battles through a colleague and becomes deeply passionate about it. He trains hard and becomes skilled enough to represent his country.During a competition, his armor fails, and he's struck in the head with a two-handed axe, seemingly dying. But is this truly the end?

After 2000 years has passed, the ruthless demon lord has just been reincarnated! But his aptitude at an academy for nurturing candidates for demon lords is, “Inept”!?

Science and Technology Library: The supreme state of science is theology; an accidental rescue, let Chen Mo get a technology library that collects endless technology, the story begins…

- Description from xbiquge translation