Replying to Grunting"ohh"

is this going around at anybody's schools?  im talking about like when people say "jea"...u kno people just saying it.  I can't really expalin it but its like a manly "oh"  in a deeper voice when something out of the ordinary happens like someone getting hurt or saying something stupid.  Example= A girl in your class says "My cat got run over yesterday." and someone says "oh" in a groaning/grunting way.
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