A rare facial expression pulled by those on the brink of falling in love, usually whilst they think no one else is watching. For example when working at a computer or watching TV.

Often accompanied by total inability to concentrate and the making of uncharacteristic mistakes - see gurple
No don't ask him, he went out with that girl again last night and now he's gurning like a hippo. He's not gonna get anything done today...
by Almosnoopy May 23, 2011
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