The Rebirth of Siblings in a Parallel World

In today's society, parallel worlds have been discovered, but they cannot pry into them. A pair of siblings accidentally opened a parallel door and entered parallel time and space. The people there were simpler and simpler than people in today's society. The siblings got along like a fish in water. Just as they were enjoying themselves, a disaster was happening. When they traveled through the door of time and space, they unexpectedly gained the power to fight against the enemy. From then on, they started a bloody confrontation. This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.