i think the boy in this story had his girlfriend pass away. after that, a person was sent to "put the color back in his world". when he lets the bird go, this is a symbol of him letting go off his troubles and worries as well.
me: im going to punch someone
me: this game is shit!
stepdad: so who are you going to punch?
me: the creator of this game
stepdad: what did he do?
me: -spins around- HE SPAWNED THIS DEMON FROM THE FIERY WRATH IT USED TO, AND SHOULD WALLOW IN AND DIE
stepdad: ... ok have fun!