What is Undie Grundie?
1.
The act of inserting a finger or thumb into an unsuspecting victims anus through their fresh new underwear, thus causing a permanent poo stain. If done in a forceful manner, blood stains may accompany the poo stains.
Paul surprised Steve with an undie grundie...a large fight insued.
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Random Words:
1.
A name normally given to adopted children who are Arabic, and are raised by a predominantly Irish family.
Also means big butt in Dearb..