Hi, I'm Jina! 히읗 is a name for ᄒ, the last consonant of the Hangul alphabet, usually represented as h in romanizations. People use ㅎㅎ for a giggle like hehe. If you saw 히읗히읗 in a text, that might be ㅎㅎ(hehe). I hope it will help you (:

ㅎ = 히읗 ‘when you read 'ㅎ’ it pronounces as 히읗. ㅎㅎ is like smiling in the text message.