Apoorv didn't know what Sagar was upto. Sagar helped him out of nowhere and rescued him from Karishma mam.

When they were climbing down the steps and heading towards the library. Sagar just tapped Apoorv's shoulder and say-Hey I got your back kiddo!!!
Apoorv was startled ,he looks confused.😶😶😶😶 Somewhat one word stops the time. He stops on the step while Sagar looks at him from the step beneath. Apoorv is nervous and just looks towards Sagar staring at him directly with his pretty face. Apoorv just stares without saying something.

Apoorv(in mind)- what did he just say! Kiddoooo.......😣 . Why do I feel so weird and this makes me uncomfortable yet I am okay with it. What the hell...... Why he looks so cute yet he makes me angry. Why 😭....... Why the word kidoooo...... Who says that......?????
Sagar(in mind)- Did I just do something, why is he staring at me like that.
Sagar waves his...