From the same phrase family as 'i have', 'i would', 'i'd tap' etc.
Used when somebody is particularly impressed by something, most frequently a person. Literally means 'I have', but said in a German accent to give it that extra 'ooft!'.
"Did you see that cumslut last night? I had her a few days ago... she walked past and i was all like 'Ooft, I haff!'"

Boy sees profile picture of hxc emo hawt grrll, and comments: NO JK JK JK LOLOLOL, I HEART UR FXCKING MAKE UP OMG I LOVE UR HAIR. OOFT, I HAFF!
by ghalighalinomnom April 26, 2009
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