What is Bum Up?
1.
a way in telling a person to "Come up"..started by 
get there stuff togetha..get fresh..Fly..ect.
-Bum Up!!
-Get like meh...BUM UP!
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2.
Pretty much the same as 'Sucking Up' to someone, except based around the action of giving somebody anal sex.
"I can believe you bum up to him just because he has a nice car."
"Dave's bumming up to Celebrities again."
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Random Words:
1. 
a person that constantly wants to be on holiday, and always finds opportunities to go on holiday, and when not on holiday the person may.. 
1. 
Forgetting the purpose of your action while conversing
Jessica suffers constantly from versanesia and returns to the dinner table with ..