You have to hug someone from behind and while you hug them you have to grab their ass.
Bro 1: That girl is thick

Bro 2: go hug her it’s National hug from behind day.
by Unknownunicorny April 17, 2019
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Hug your boyfriend/girlfriend from behind and make them feel loved
“National hugs from behind day is my favorite day!”
by Lacnicpat2002 October 21, 2019
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