(This story is based of inspiration from GATE. Will take suggestions for future chapters and OCs.) While an off duty marine is on a cruise, the ship he is on is boarded by medieval soldiers from another world. People are taken and in retaliation, the US send a fleet through a portal to get their people back. But when slavery exists in this world, they also bring liberty with them.

The tomb of the Indigo Dragon Empress was disturbed and grave robbed by two fallen angels. While two of the three mystic weapons were stolen, only one was saved. The Empress' spirit awakens to find a host to partner up in order to seek revenge on those who disrupted the empress' slumber, but her host she must rely and trust, is an average teenage boy from another world. (OCxHarem)