I, Kiriko, the Cheater

"Four Holy Heroes who obeyed the call, please listen to our request... Wait, wait a minute, why are there five of the legendary Four Holy Heroes? This is different from what we said!"
……
My name is Kiriko, and as the fifth of the Four Holy Heroes who have been summoned to this world, I don't have the legendary weapons that other heroes have given me at the beginning of the game, but I have an advantage that other heroes don't have...
I can upgrade duck infinitely!
……
In short, this is the story of Kiriko's travels in various comprehensive worlds.