They won the Holy Grail War, but this turned out to be the Virtual Tree Universe.

Danlei, who traveled through the Type-Moon universe, risked his life to win the Holy Grail War and wished to return home in order to escape the terrifying timeline containing Chaldea.
As a result, the Holy Grail can only send people away from the origin of this world.
Furthermore, this is the Type-Moon world connected to the Tree of Imaginary Numbers.
Danlei: I wished to go home, but how did I end up in the Star Iron Universe? And I even became a member of the Wisdom Dragon Clan!
It's alright, the Holy Grail is still there, and I'm an immortal being. At worst, I can just wear it again after I've used up all my energy!
Oh no, both balance and memory are targeting me. Why is it that every time I travel to a world, it's based on my own memories?
With two star gods joining forces to "serve" him, Dan Lei said he was incredibly lucky in his life.
So Danlei began to travel with the heroic spirits to various worlds.
He calls himself a patrolling sea knight in the Demon Slayer world, cosplays the Last King in Under One Person, and impersonates the Interstellar Peace Corporation in the Super God Universe...
When Dan Lei returned to the Type-Moon world, looking at Fujimaru Ritsuka struggling to save humanity, Dan Lei sincerely said...
"The heroic spirits aren't strong enough? Check out the fictional historians."

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