A small face with a single sweat drop. The eyes ・ are minimal dots, the mouth _ is a flat line, and the semicolon ; on the right is the kaomoji convention for a bead of sweat sliding down the face — usually meaning nervousness, awkwardness, or ‘this is uncomfortable.’
The minimalism is the whole point of this kaomoji. It is one of the simplest expressions in the entire kaomoji vocabulary. Just dots, a line, and a sweat drop. That bareness makes it read as understated: the person is uncomfortable but trying not to make a scene. It is the kaomoji equivalent of an awkward half-smile when you do not know what to say.
Use it in conversations where you encountered something a little awkward or worrying: a friend overshared, you got asked a question you cannot answer, you saw something you wish you had not. It works on Discord, Twitter/X, and in chat replies generally. Because it is so common in Japanese text-message culture, it is one of the first kaomoji that older Japanese phones suggested under ‘troubled’ or ‘nervous.’
The matching Japanese expression is あせる (aseru — to be in a hurry or to break a nervous sweat). Pair with words like えっと… (‘etto…’ — ‘um…’), どうしよう (‘dou shiyou’ — ‘what should I do’), or simply silence — this kaomoji often follows a moment when you are not sure what to say.