Fate/Saber - Legend of Arthurian and Seiken

Once upon a time, there was a boy that came from different world known as Wonder World. A world that is a colorful fantasy world, populated not only by humans, but also by different creatures, mechanical God Beasts, Animals and Story Characters.

The boy in none other then the new Guardian and successor of the 11 Seiken. But now, Wonder World in peace thus he decided to travel and upon arrival, he end up in Alternative Legend of Arthurian.

What will this Guardian and Knight will do upon meeting the female Arthur? What kind of situation will arise when he meet Morgan? Will a love bloom between any of them? This a tale where no one ever heard as prepared yourself as this story will surely get interesting.