According to the Buzzfeed video article found on Snapchat, “U up?” means do you want to have sex? “U up?” is a text message that is usually sent at late hours of the night and usually imply, if you are up, that you want to hangout and engage in sexual activity. This is also known as a booty called. It infers that you would like to meet up with each other. More information can be found at https://www.buzzfeed.com/elivazquez/what-does-the-u-up-text-mean
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