It's so much brighter outside

When there is no monster lurking outside to cause you fright
                 Because they don't come out in broad daylight
When there are no shadows that enormous dark clouds cast
                 For there isn't a single bad weather forecast
When there's not one thief to steal the worth of your toils
                Since they've all left to eat others' spoils
Then there's no reason left for me to dwell
In the darkness of my impenetrable shell
Because in my gloom, I must not reside
When it's so much brighter outside