Blueface, 26, made the claims amid a series of tweets on Sunday.
Offset has reacted to allegations that he slept with Chrisean Rock, the babymama of rapper Blueface.
He denied the allegation.
'I ain't never talk or touch that lady,' the 32-year-old rapper, whose real name is Kiari Kendrell Cephus, said in response to Blueface's claims. 'Real talk man you need some help!'
Blueface, 26, made the claims amid a series of tweets on Sunday.
Blueface, whose full name is Johnathan Jamall Porter, said in a tweet, 'Being tatted on a h** is not a flex you literally f***** cardi B husband couple weeks ago I’m tired of n***** looking at me while they f****** you get the rest of em gone asap please.'
Blueface said, 'Tried to keep yo secret but you keep popping it on these apps ima only state facts everytime ... So you ain’t f*** cardi husband November 10th at 4am at their house in LA …I’m making this up ? ... Post that time an date on they a** now everybody quiet.'
He also retweeted a follower who said of Chrisean, 'Chrisean quotes the Bible then sleeps with a married man.'
Chrisean appeared to deny the allegations, saying in a tweet: 'U just crashing out making up s***.'
Chrisean also alleged that she 'saw Gay porn' in Blueface's 'recent search history,' adding, 'Nothing wrong with being bisexual just let a b**** no before she fall in love weirdo.'
Blueface replied, 'Now I watch Gay porn ... that’s the best you could come up.'
Blueface said of the social media stir he caused, 'Hurricane blue has hit an wiped everyone off the app….we will take a brief commercial break till someone is feeling froggy again.'
He added that he 'everything' he said was 'factual' and that he's not deleting any of his controversial statements.
The exchange came amid speculation that Cardi B's relationship with Offset might be in crisis after they had unfollowed each other on social media earlier this month.