Nemui Genjutsu

The back and forth of Nemui attacking and Itachi dodging gracefully lasted
about ten minutes. Just when people in the arena were starting to fuss about
the lack of any real developments, it happened.
Nemui stopped abruptly, shook faintly, and lifted his closed eyelids the
tiniest bit. Their eyes met.
This was the moment Itachi had been waiting for. He poured his chakra
into his eyes.
Sharingan. It took less than a hundredth of a second to activate. Itachi was
betting on that moment. He hammered into Nemui’s pupils the detailed
image he had drawn in his mind while dodging attacks.
“Eee!” Nemui shrieked. Awake for a mere instant, he fell asleep once
more.

I did it ...
He slipped around from the rear, and slit Nemui’s throat with his kunai.
The image Itachi had imagined so faithfully, down to the very last detail,
became reality, replaying in his enemy’s mind. Nemui died, his throat slashed. But he was aware that he was still alive, and he opened his eyes again. But he couldn’t sleep as soundly anymore.

Itachi dodged Nemui’s attacks for a few minutes, but then his opponent’s
eyelids fluttered once more. In an instant, his field of view was dyed red.
This time, the image was of Itachi gouging into his stomach.
Repeat.

Each time he was killed, Nemui’s sleep grew lighter. Stabbed, strangled,
beaten, poisoned; Itachi killed the boy any and every way possible.
Finally, Nemui couldn’t sleep at all. If he closed his eyes, Itachi would kill
him. After being subjected to brutal deaths over and over and over, he was
now completely ruled by his fear of the final sleep.

“Eee ... Eee ... Eee ...” Chest heaving, almost hyperventilating, Nemui
trembled and shook.
The spectators had no idea what was happening. At best, only a few people
there had realized Itachi was using the sharingan.

Itachi continued to evade his attacks, while Nemui’s movements gradually
grew sluggish. Sweat streamed down Nemui’s face; he started to cry. Itachi
hadn’t once used a physical attack on him.
“H-help me,” Nemui groaned in supplication. He fell to his knees and
began weeping loudly. “I-I don’t want to die anymore! Please, help
me ... Please.”
“We have a winner!” The examiner stepped in between the two of them.

Book of Bright Light Chapter 3 Part 1