From the Start, I Found the Nine-Zhang Golden Body Manual on the Seabed

When the young fisherman Luo Tian went out to sea, he rescued a beautiful woman.

She offered to give herself to him once her injuries healed.

Luo Tian took the savings his grandfather had spent most of his life putting aside as Luo Tian's future dowry and used them to heal her!

But once she recovered, she not only went back on her word, she also tried to kill him while they were out at sea!

Luckily,

Luo Tian obtained the Divine Mirror of All Things, which lets him see the attributes of everything and understand all things!

On a deserted island, while everyone else fights desperately over those brightly colored poisonous fruits, Luo Tian calmly picks the ugly black spirit fruit!

At an auction, while everyone else bids sky-high for the sword that rings out, Luo Tian calmly buys the rusty divine spear!

In a flower-bedecked bed beneath the spring canopy, while others impulsively pounce on the alluring beauty, Luo Tian calmly stabs the bewitching demoness to death!

P.S. This book is also known as "Fantasy: I Can See the Attributes of All Things."