I was listening to Alligator Sky by Owl City and realized how munch the song describes Asriel.

The chorus:

Where was I when the rockets came to life and carried you away into the Alligator Sky?

Even though I'll never know what's up ahead, I'm never letting go, I'm never letting go!

Even though he doesn't know what'll happen when he arrives to Chara's village, he's never letting go of Chara, no matter what.

And also, and I quote: "I don't want to let go." ~Asriel Dreemur, 2015

That might not be exactly what he says but I'm too lazy to check the Wikia to see the direct quote.

Then:

Remember to dream, because it's gonna be a starry night, over every town if you look down. So harmonize with the singing satellites!

I'm drowning in this starry serenade.

I'm scared to death that I'll never be afraid.

And remember to laugh because you're living in a crazy world where you'll never guess what can happen next.

That was just a bunch of lyrics that sounded like Asriel, I'm not quite sure why.