Noah couldn't stop suffering injuries during the battle. He was against a rank 8 magical beast, and he wielded three cursed swords. Each clash brought his body to its limits.
Yet, his flames allowed him to recover instantly. Noah would be fine as long as the environment had nutrients to burn and the monkey didn't manage to kill him in one blow.
On the other hand, the monkey had the resilience of a rank 8 magical beast. It was almost immortal in the eyes of rank 7 beings. It didn't matter how many injuries it suffered. The creature always straightened its position and launched its threatening soundwaves.
Noah never stopped leaping toward the monkey. His slashes would deal more damage if his blades touched the creature's skin, so he couldn't deploy safer tactics.
Moreover, the soundwaves damaged the monkey whenever they exploded next to it. Noah slowly gained the upper hand in the battle after forcing many attacks to detonate in front of his opponent.