Online Games Two Dimensions: Starting Contract Hall

I accidentally traveled to a parallel world and discovered that this world actually has online games that can synchronize reality. The world of online games is actually a two-dimensional world, and there are actually no two-dimensional works in this world. The protagonist is the only person in the plot. Not only that, the protagonist also obtains demi-human blood at the beginning and a contract palace that can contract with characters in the game world. Let's see how the protagonist leads the two-dimensional girl army to conquer various worlds. This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.