As far as we can tell, the Creator is not an actual character. That image is taken from a fan translation, and the equivalent line from episode 4's vn is this:
== Beatrice ==
「うむ。造物主の道を求める魔女の称号よ。今は身の回りの小物に魔力を吹き込む力しか持たぬ、エンチャンター(付与魔術師)でしかない。
"Indeed. It is the title of a witch who seeks to become a Creator. Right now, you are just an Enchanter (a magician specializing in forms of magical enhancement) who has only enough strength to breathe magical power into the small objects around her.
……しかし千年の修行を経たならば、その胸の内より魔法大系はおろか、銀河を生み出すことも夢ではあるまい。」
...But after one thousand years of training, you could conceivably use the magical compendium that resides inside your heart to create a galaxy."
Creator is meant to be a rank that a witch could get, not the literal Creator of everything