The idea is ok. The game is too simple in my opinion, should have some type of enemy or something so it is a "challenge".
Some things I would improve:
-Camera control feels strange since it is inverted. I would not invert it.
-Movement feels slow and floaty. Would add more gravity.
-A record of what's the fastest time that you found your twin.
-Some enemy.
-A trigger so if you fall off the map you spawn in it again
Good job!