姑娘你骚得像我大姨妈
[gū niáng nĭ sāo dé xiàng wŏ dà yí mā]
In a colloquial context and not very polite, it roughly means 'Girl, you act like a menstrual period' which could refer to someone's moodiness or unpredictable behavior likened jokingly to the monthly cycle of women using somewhat harsh wording. (Please note: The expression may be deemed inappropriate.)