What does it feel like to have warmth and tenderness in your arms?
In all honesty, it's quite pleasant.
But what does it feel like to be constrained by warmth and tenderness?
Not so pleasant.
It wasn't too bad with Su Yunjin; she just squeezed into Yan Yu's blanket and clung to his right arm, shivering—the equivalent of having a fragrant and soft accessory hanging off his arm, which didn't really hinder his movements.
However, Lin Ning forcibly bent his left arm towards her—both scared and apprehensive to crawl into the bed herself, she simply "snatched" a sense of security for herself, making Yan Yu feel as if he were shackled by human-shaped handcuffs.
The softness was indeed there, but being hugged by Lin Ning, who also clamped his hand between her legs, meant he was completely immobilized, which obviously wouldn't do.
After Yan Yu had tried in vain to withdraw his arm for a long time, he could only send a message to Lin Ning with his thoughts: