The female officer on the third floor drew her bow back to its limit, her aim fixed on him, and loosed three golden arrows simultaneously. They inscribed a triplicate curve as they sped towards Jester’s heart at nearly the speed of sound. As the arrows approached him, however, their radiance began to dim. By the time they reached him, they were ordinary iron arrows, which bounced off Jester without so much as ripping his suit.
He had not moved at all. The arrows had been thwarted by his skin.
It was not as though he had turned to steel, or sprouted scales like a dragon; the mach-speed bow had had failed to penetrate what appeared to be nothing more than soft, fair, human skin.

Fate/Strange Fake: Volume 2, Chapter 3 ("Day 1, Early Dawn")