Ara ara (あらあら) is a Japanese expression that is used to express mild surprise

ara ara meaning is a Japanese expression that is used to express mild surprise, and is an exclamation similar to, “oh dear,” “my my,” “oh me oh my,” or simply, “oh my!” in English. The meaning behind “ara ara” depends on its context of use. The phrase is typically said by women as an interjection to express surprise, compassion, affection, or disapproval.
In anime, however, it is usually used in a suggestive way towards younger men by gentle, adult-like, or motherly female characters. It can convey sexual intentions or flirtatiousness. This usage of “ara ara” has become popularized in memes and fan art in the English-speaking world.

You can find more examples of how “ara ara” is used in different situations on these websites wiki mean.