It seems that the world itself is tested by tribulation lightning and prelude disasters.

The last time it happened 500 years ago, huge sacrifices were made by the cultivation world, and the immortal tree yao was killed and made into immortal cauldrons that suppress the world's disasters.

The ML is a living battery, able to absorb insane amounts of spiritual energy and use it to charge the immortal cauldrons to keep the world safe.

The FL was supposed to be reborn as the next immortal tree, but that requires the parts of the previous immortal tree that were made into the immortal cauldrons. If she took them out, the cauldrons would fail and the world would plunge into disaster. So she chose to remain as a garlic chive yao to protect the world. She's still OP, though.

At the end of the plot, they realize they don't need the continual use of the cauldron/ML/immortal tree to prevent disaster. Instead, if they can only withstand the tribulation lightning long enough, the heavenly disaster would pass on its own.

At that point, the cauldrons break, the different peoples unite to protect the world, they manage to pass the tribulation lightning, and the world is restored/peaceful again.

MC is the young master of the yao clan. She is a garlic chive but can become the divine gan tree if she recovers the bones of the previous gan tree. The bones were used to produce ten cauldrons. These cauldrons were infused with spiritual energy each year to prevent the earth's calamity.

The person who infuses the energy is ML, Immortal Lord Fuguang aka Zhi You. ML had been "imprisoned" on Fuguang Mountain since he was a baby. His role is to collect the world's spiritual energy for the cauldrons.

About 500 years ago, he found a garlic chive when he went looking for his mother. He took it back to Fuguang Mountain and raised it. But 18 years ago, it disappeared. So he dug out his heart and made his other self, Zhi You. As Zhi You, he went looking for the garlic chive while Lord Fuguang was also able to stay on the mountain.

He met MC and joined a sect with MC. He was able to know the goodness of the world and fell for MC. The funny thing is he learnt how to be a white lotus by reading romance novels, written by their senior sect brother, and gain MC's affection. 😂

A lot of stuff happens in the plot so I'll summarize it that ML was able to permanently leave the mountain and the world was still able to be at peace. And ML achieved his dream of marrying into MC's family. 🥰

And yes, MC was ML's lost garlic chive. A cultivator used a soul summoning spell that caused MC to disappear and end up being found by her village elders. She was then adopted and spoiled by her elders.

ML is in a one-sided crush/love for 90% of the novel, so there was no fluff. First romance novel I've read that didn't have even a kiss.