Fate/Gay Order

Main Character: How did this happen?

Earlier in Fuyuki....

Irisveil: Congratulations final master, what is your wish?

Unnamed Master: I want to recreate the world in my image! A world of yuri!

Irisveil: You realize that means that all men in the world will die.

Unnamed Master: I don't care! I want to create paradise!

Irisviel: As you wish.

….And thus Singularity L was created.