The Monkey King attacked Ye Wudao from behind, and it was very fast, but Ye Wudao didn't want to hurt it, so he spread his Inner Qi all over his back to form a defensive zone.
The Monkey King's claws scratched at Ye Wudao's back, but it didn't harm him as it had expected. Instead, it felt like it was scratching against a hard rock, which made it yelp in pain.
Clearly, with the Monkey King's brain capacity, it was difficult for it to understand why the body of the creature before it was so hard. However, this did not deter it; it immediately changed its strategy, grabbing a vine and swinging away. Just when Ye Wudao thought the Monkey King had retreated, a gust of wind came from above his head, and the Monkey King was back, this time aiming not for his back but trying to gouge Ye Wudao's eyes.