How does multiplayer work in Divinity Original Sin?

There are only 2 people allowed. The host of the game controls one of the two main characters, the second player has control over the second main (wow- surprise, isn't it). So basically, host invites the other player (also possible while creating characters) and afterwards saves/loads the game, assigns additional 2 characters among players. Note that the player who joined the game is not allowed to play as long original host didn't invite them.