Kevin grabs Blanka's hand and gets up. He blushes from what Nai said.

-What are you talking about? He's not into guys, and neither am I.

He lied. Kevin is gay, but he doesn't have the guts to tell anyone about it. It's mostly because of the bullying.
Before he opens his mouth again, he sees Nai taking his phone from the ground.

-What are you doing? Give my back my phone! Please!

When Nai hands him his phone, he sees their little bit worried faces. Mostly Blanka's.

-Guys, why do you look at me like that? I-I'm ok! 

His lie is so obvious that everyone in the world could see it.