I think I've been transported

In a world ruled by swords and magic, Jade lives a quiet life of training and survival—until everything is taken from him. A mysterious enemy manipulating demons from the shadows launches an attack, and amid the chaos, Jade’s twin sister, Arian, suddenly vanishes. All that remains is a strange, special rift that appears without warning, never opening in the same place twice. Refusing to lose her, Jade leaps into the rift after her—only to be thrown into an impossible world. Magic is gone. Dragons are myths. Instead, towering glass buildings pierce the sky, and roaring metal creatures race across stone roads without mana or beasts to guide them. Cast into modern Earth, Jade’s understanding of strength, battle, and survival is completely overturned in a world ruled by technology rather than blades. Now stranded between two worlds, Jade must adapt to Earth’s unfamiliar laws while searching for any trace of his missing sister. Can he find Arian in a world that should not exist to him—and discover a way back home before both worlds are swallowed by the same unseen enemy?