Arriving from school exhausted, a portal suddenly opened in front of him after making contact with an object that materialized out of thin air in his house. 
As a result, he was pulled in and dropped into a dark area with a bed in it. He thought he was dreaming but after a few reality-checks, he realized that didn't turn out to be the case.
Afterwards, he began to feel sleepy and tried sleeping on the bed. But, the moment he opened his eyes, It wasn't a world he was used to. He woke up in a normal room this time but it was different. It wasn't his room nor did it look like anything like from the world he used to be in. After looking around, he decided to get out of the room only to meet a girl by the hallway. He soon found out that she came from a parallel world and that both of them had the same name, same interests, and the same personality. They didn't suspect each other. INstead, they decided to work together to explore this world they found to be in.

Can they survive in this world?