Monogamy

To Gu Chengyin's repeated confirmation, Shangguan Yunying gave an affirmative reply.

After all, since Luo Zhao wouldn't allow Gu Chengyin to touch her, rounding things off, the only option left was to have Gu Chengyin touch Luo Zhao.

But seeing Gu Chengyin's hesitation, Shangguan Yunying knew that without a convincing reason, given his cautious nature, he definitely wouldn't do such a thing easily.

Today was different from yesterday. Yesterday was a test, done by Gu Chengyin to put her mind at ease.

But right now, this was completely out of nowhere; no matter how you looked at it, it seemed like a massive trap.

So Shangguan Yunying closed the distance, leaning in close to Gu Chengyin's ear and whispering,

"Have you ever thought about..."

"Why you are able to weaken Lord Jingzhe's inner demons?"

Gu Chengyin had actually pondered this question, so he asked in return,

"Is it because I resemble Empress Lin?"

"Exactly!"

Shangguan Yunying's eyes lit up. She even clapped her hands lightly, the movement very subtle.

"Since even you can weaken Lord Jingzhe's inner demons, then tell me..."

"As Empress Lin's biological daughter, couldn't Her Highness do it too?"

Gu Chengyin nodded, agreeing with this logic.

"Theoretically, yes."

Shangguan Yunying shook her head to clarify,

"It's not just theoretically, she really can."

"Her Highness even offered to help on her own initiative, but Lord Jingzhe refused her."

"Do you know why?"

Gu Chengyin didn't answer immediately. His mind raced.

Why?

Because Lin Qingyan was Luo Zhao's aunt, her elder.

And to have Luo Zhao help weaken the inner demon would mean exposing her most vulnerable and unbearable side in front of Luo Zhao.

That is, the inner demon Lin Qingyan who hugged his arm, acting spoiled and sweetly calling him Master.

For Lin Qingyan, this would probably be unacceptable.

"Because..."

Gu Chengyin spoke, his voice very soft.

"Lin Qingyan is Her Highness's aunt, her elder. And to weaken the inner demon, one would have to..."

He didn't finish his sentence, his gaze already falling upon Shangguan Yunying.

The implication was self-evident.

Shangguan Yunying nodded gently.

"So," she said, "I was thinking..."

She paused, her gaze sweeping back and forth between Gu Chengyin and Luo Zhao.

"Since you resemble Empress Lin, and Her Highness is Empress Lin's biological daughter, and both of you can weaken Lord Jingzhe's inner demons..."

"Then what if, and I'm just saying what if..."

"You two combined?"

Gu Chengyin: "..."

Combined?

Combined how?

Did she mean combined in the way he was thinking?

"Yunying, what do you mean by that?"

"I mean it literally."

Shangguan Yunying wore an innocent expression on her face, but the slyness in her eyes betrayed her true thoughts.

"Since you can weaken Lord Jingzhe's inner demons."

"Then if you and Her Highness were more intimate, wouldn't the effect be better?"

"It's like an herbal catalyst. Used alone, it can cure a disease, but if paired with other medicinal herbs, the effects are multiplied."

Gu Chengyin fell silent.

He stared at Shangguan Yunying, trying to find a trace of a joke on her face.

But there was none.

Shangguan Yunying's expression was incredibly serious, her eyes as clear as a mountain spring, devoid of any impurities.

But the more she looked like that, the more absurd Gu Chengyin found it.

Because this line of reasoning actually had a scientific theory to explain it.

Microbiome exchange.

Through long-term intimate contact, exchanging microbiomes causes couples to look more and more alike.

This is the so-called husband and wife resemblance.

But that is built on the foundation of living together long-term.

It takes time.

It requires countless intimate contacts.

"Yunying."

Gu Chengyin took a deep breath and asked cautiously,

"Do you know about microbiome exchange?"

Shangguan Yunying blinked, a flash of confusion passing through her eyes.

"Micro... what?"

Just as I thought.

Gu Chengyin sighed inwardly.

Shangguan Yunying knew nothing about biology, nor any microbiome theory.

She merely relied on intuition, on some almost instinctual understanding, to propose this absurd idea.

But the absurd part was that this proposal actually had logic to it.

If Gu Chengyin resembled Empress Lin, and Luo Zhao was Empress Lin's biological daughter.

Then if he kissed Luo Zhao, there would naturally be a microbiome exchange.

This would indeed make Gu Chengyin resemble Empress Lin even more.

Combined like this, it really might achieve an effect where one plus one is greater than two.

"So..."

Gu Chengyin looked at Luo Zhao, then back at Shangguan Yunying.

"You want me to kiss Her Highness for the sake of Auntie's inner demon?"

"Mm."

Shangguan Yunying nodded, her expression taking it as a matter of course.

"You're setting off tomorrow. What if Lord Jingzhe has problems again?"

"So I thought, why not take this opportunity for you to have more contact with Her Highness."

"Even though we don't know if the effect will be good, it's better than nothing, right?"

Gu Chengyin's eye twitched. The logic was there, and it did sound quite reasonable.

But why did it just feel so weird?

Of course, Shangguan Yunying was genuinely doing it for his sake. After all, not just anyone could watch the person they like kiss another woman.

Gu Chengyin thought it over and said, "Yunying, I understand what you mean."

"It's undeniable that you're very smart, because this actually could work, but it's not something that can be achieved with a single kiss."

"It requires long-term, intimate contact to form over days and months of accumulation."

Just as Gu Chengyin was pondering how to explain this microbiome exchange.

He saw Shangguan Yunying's eyes light up as she suddenly said,

"You mean, as long as you kiss Her Highness every day, it will work?"

Gu Chengyin: "..."

He said, somewhat caught between laughter and tears, "That's the logic, yes, but she is Her Highness. No matter what, we can't just..."

Shangguan Yunying revealed a confused look, tilting her head as she asked,

"But isn't Her Highness hypnotized by you? Let alone kissing, even if..."

Shangguan Yunying originally wanted to mention what happened last night, but she couldn't quite bring herself to say it, so she could only change the subject.

"Anyway... as long as I don't tell, no one will know what you did to Her Highness~"

Gu Chengyin's heart involuntarily went on alert. He stared at Shangguan Yunying suspiciously and asked,

"Yunying, why do I feel like something isn't quite right with you?"

"Are you really doing this to weaken Auntie's inner demon, or..."

Gu Chengyin tried to find a reasonable explanation to describe Shangguan Yunying's behavior.

But no matter how he thought about it, he couldn't find one.

It wasn't until he saw that Shangguan Yunying was wearing the exact same nightgown as Luo Zhao that a shocking thought flashed through his mind.

He couldn't help but exclaim in shock,

"You want one husband and one wife?!"

This phrase completely baffled Shangguan Yunying. It took her a long time to understand what Gu Chengyin meant by one husband and one wife.

Her face quickly flushed red, and she couldn't help but smack Gu Chengyin, scolding playfully,

"What are you talking about! That's such a weird way to put it!"