i was his best friend. inseparable. but now he no longer needs me. based on NCT 127's 'No Longer'

Seo Soojin is a teenage girl. Due to things that happened in the past she became the school Bully. A boy appears, and he's the only one that saw a good side of her. He slowly falls for her, even though she rejects him, he's not giving up. She's the only one for him, and he's the only one for her...