Being Jun's partner is a bit complicated, he's a boy who wander in his own world. Due to internal problems, his only escape was boxes full of harmful nicotine and bad company, until he met you

He tried to stop making bad decisions, he wanted to be a better person just for you. But he felt guilty for give in to his impulses again and again

Both were lying on your house's sofa, his head resting on your chest. He had that urge to go smoke to again. Nicotine doesn't let him progress