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Best Sister In The Whole Universe and Beyond
-ITWUAB: greatest and sweetest extension.

can also be used in other words.

bsitwww, (best sister in the whole wide world) or bbfitwuab, (best boyfriend in the whole universe and beyond)
"She's definitely my bsitwuab!"

"Wtf? What's that?"

"It means best sister in the whole universe and beyond. You're just jealous" <3
by fagbag v2 June 26, 2010