If you don’t hurry up, it will get dark.
Remember how you learned that 暮らす means "to live?" Well when you're in too much of a rush (らす) to live life to the fullest, you won't notice it start to get dark. You try to live day and night until it starts to end. Shine on in that darkness!
Since this word consists of a kanji with hiragana attached, you can bet that it will use the kun'yomi reading. You learned this reading when you learned 暮らす, so if you can remember that, you should be able to remember this one too!