noun
ahegao; exaggerated sexual facial expression
Slang from manga/anime culture; describes a stylized, exaggerated facial expression (often with rolled eyes, protruding tongue, flushed cheeks) typically associated with intense sexual pleasure, usually depicted on female characters.
その同人誌の表紙にはアヘ顔のキャラクターが描かれていた。
The cover of that doujinshi featured a character with an ahegao expression.
アヘ顔はネットミームとしても広まった。
Ahegao also spread as an internet meme.