Shalltear catches God Flash

However—
Shalltear had caught it with her fingertips.
She had caught Brain’s lightning-fast strike.
In addition, she held his blade gently, like one would the wings of a butterfly.
Brain could not help but pant heavily, as he felt the air seem to freeze around him.
“...Im-Impossible...”
Those nearly inaudible words accompanied each gasp he made.
Brain struggled desperately to rein in the tremors within him, as the scene before his eyes utterly defied his expectations. However, it was an undeniable fact that there were two of Shalltear’s ivory fingers upon the body of his blade — her thumb and her forefinger.
More than that, she had not seized his blade from the front, but hooked her arm around the swing to catch it from behind. Without once entering the path of the strike, she had caught up with the speed of the katana — with the speed of his [God Flash].

[...]

“Hmph, Cocytus has several of these too, but since there’s an astronomical difference between the wielders, it’s hardly worth being on guard for.”

- Overlord; Vol 3; Chapter 2