ㄹ라

'Watch out, X might happen'

-ㄹ라 warns that something bad is coming if nobody is careful: 조심해! 치즈 흘러내릴라...! 'careful, the cheese is going to run off!' and 큰형 깨실라... 'you'll wake him up.' It is casual, spoken, and aimed at whoever is about to cause the problem. Several lines here (트랄랄레로, 라라랜드, 지슬라, 훌라) only contain the syllable and have nothing to do with this ending.

Register: casual warning