"发出咂咂声的人" can be translated into English as "a person who makes smacking/slurping sounds" or "someone who smacks/slurps".
"Smacking" often refers to the sharp, clicking sound made with the lips, such as when savoring food or expressing approval.
"Slurping" typically describes the sound made when sucking in liquid noisily, like when drinking soup.
Choose the appropriate verb based on the specific context or the type of sound being made.