Where it comes from
The ゞ (a Japanese iteration mark) is the hand raised to the forehead.  ̄ are serious, flat eyes and ^ is a firm, pursed mouth.
When to use it
Use it to accept a task, confirm plans or cheer someone off. It's casual and cheeky, so keep it out of formal replies.
Examples
- Got it, I'll bring the snacks ( ̄^ ̄)ゞ
- Mission accepted ( ̄^ ̄)ゞ
Variants to copy
What it is made of
Every character in the face with its Unicode code point — handy if one shows up as a box on a friend's phone.
(
U+0028left parenthesis ̄
U+FFE3fullwidth macron^
U+005Ecircumflex accent)
U+0029right parenthesisゞ
U+309Ehiragana voiced iteration mark