When I Woke Up, My Sister Turned Me into a Girl

Song Yuan woke up and became a girl, and was sent to middle school to study again by her sister. He wanted to resist, but his sister gave him too much. I thought it was just a ridiculous gender switch, until a campus attack occurred - the latent war was ignited again. The empire expands, the Federation coups, and old comrades and new enemies meet again. When a battle-hardened veteran is trapped in the body of a girl and campus life, Can he regain his hands on that familiar rifle and once again protect everything he cherishes on the ruins of peace?