Bound by Marriage

It was clearly an object of special significance to its owner.
The girl paused for a moment, then scanned the QR code. The account displayed: AA - Locksmith General Cheng Li. She bit her lip and quietly asked, "Brother... are you married?"
Cheng Li didn't hide it: "Yes, married for two years now."
The girl still mumbled, "Why so early? You look like you're only in your early twenties..."
"It is an early marriage, isn't it?" she concluded.
Cheng Li just smiled: "Because that person is too good. I felt it would be a pity to miss out. So I wanted to use a method that person likes to bind myself to him."
Pei Su was a genuine human, with human thoughts and rituals. Between people, if they loved each other, the best way to bind the other person was through marriage. He couldn't actually bind Pei Su to his own body, merging into one, as the system once suggested; that was the way of monsters.
Cheng Li didn't want to become a monster, nor did he want to do anything illegal that would make Pei Su despise him.
He wanted to marry Pei Su, because he wanted to become a... human that Pei Su would love.

Cheng Li smiled as he saw the girl into her house. After seeing her lock the iron door, he dropped his smile and turned to look at the apartment opposite, his eyes becoming a little strange, as if behind that old iron door, something was flourishing.
His intuition told him to check it out. Cheng Li always trusted his intuition, because it was something honed through countless life-and-death situations in various instances.
He tilted his head, knocked on the door a few times, but no one answered.
So he took out his phone and started searching Google: "How many years in prison for breaking and entering?", "What crime is it?", "Can I avoid prosecution?"...
Finally, Cheng Li scratched his head and sighed, concluding: This door must be broken into, but absolutely no one must know.
Therefore, he closed his eyes, gently poking the system, which was enveloped by countless nerve cells, in his mind. A green light flashed, data flowed around the system. Then, Cheng Li saw the surveillance camera facing him suddenly flicker with white noise, a screen full of garbled characters.
Cheng Li opened his eyes with satisfaction, casually pulled the lock off the iron door, pushed it open, and stepped inside.
The scene inside unfolded before his eyes: a bizarre green vine, with tangled roots and winding, overlapping stems. Its tip continuously pushed against the ceiling, and cracks spread from its branches, as if it wanted to pierce through the entire room.