Prompt: "My request would be Shirou summoning Merlin and seeing the ensuring fallout/shenanigan's happen." — Knight_Of_Rebellion
"...only those free of sin may pass."
His staff struck down into the sea of flowers.
"Garden of Avalon!"
The ground shook violently. An earthquake was splitting apart the street before them, and Shirou stood agape as a nearby skyscraper crumbled to pieces, scattering concrete dust. In its place, a long, ivory and golden tower tore the skyline asunder, casting a shadow over them.
"A beautiful prison," the Mage of Flowers said, turning to him, "but a prison nonetheless. No one in this city will be out of my sight now. Is that what you wanted?"
"I just wanted to see if there was a sale at the market today!" Shirou yelled indignantly. "I didn't ask for this!"
"Oh." Merlin faced the tower again, scratching his chin. "Hm. Well... I can make it go away again."
"And make everyone forget about it?"
"Ahah..." The mage chuckled awkwardly, scratching the back of his head. "...no?"
"Are you kidding me?!"
"I can... maybe make it look pretty?"
"Shirou, what the fu—" Shirou cringed instinctively as he heard Tohsaka approach.
"No, no, this was me," Merlin assured her. As her glare turned to him, he smiled brightly, trying to assuage her further.
Rin slapped him.
"You useless mage!"