I feel like the whole song is a metaphor. He's in a relationship that he wants to keep secret and away from the public eye.
"You don't know what they're like , if they know that you're alive "
He's talking about the paparazzi/ fans and how if they find out there will be a lot of hate etc and people bombarding her . And him being Justin Bieber knows exactly what this is like .
"Stay in my backpack forever"
He wants to keep it a secret forever.
"I can't stay in your backpack forever"
She's saying they can't hide forever.
I feel like the whole song is a metaphor. He's in a relationship that he wants to keep secret and away from the public eye.
"You don't know what they're like , if they know that you're alive " He's talking about the paparazzi/ fans and how if they find out there will be a lot of hate etc and people bombarding her . And him being Justin Bieber knows exactly what this is like .
"Stay in my backpack forever" He wants to keep it a secret forever.
"I can't stay in your backpack forever" She's saying they can't hide forever.