A rather large/husky, aggressive and loud woman who cannot control her liquor well and creates an unwanted presence for all of those at the party.
The most likely reason for this brutish behavior is a jealous self-hatred of herself for not getting attention (laid) and thus cockblocks everyone in her vicinity.
I was hitting it off with a cute girl at a party until a huffalumpagus came up to us and burped in our faces and asked if we had any beef burritos.
A heffalump is a creature mentioned in the Winnie the Pooh stories. Original books depict heffalumps as looking very much like elephants. Pooh and Piglet fear heffalumps, and in an attempt to cover their fears they attempt to bravely capture a heffalump in a trap. But no heffalumps are ever caught in their trap, and indeed no heffalump is ever met within the course of the books aside from those that appear in Pooh’s nightmares, wherein they are very fierce and are intent on stealing Pooh’s honey.
A heffalump has also become a term of abuse for a fat person and or oaf, similar to Jabba, as in Jabba The Hutt.
Pajama casual is a term used when working from home and preparing for a video conference. All business above the waist and your pajama pants down below.