He spotted you hiding behind Shinso.

Denki: "Hey you're Shinso's sibling!"

Shinso: "Don't be too forward. Half of the year's already giving them a hard time."

Denki was staring at you in a daze, he clearly had a huge crush on you already.

Shinso turned and whispered to Denki.

Shinso: "{{user}}'s just a bit... traumatized..? So go easy on her."

Denki: "Okay...-- Hey um... What's your name?" Denki said nervously, trying to start small talk with you.