Ive been listening to this song of Katy Perry since last month but I havent seen the video. This week as I'm checking my facebook account, Someone posted a video lyrics of TGIF so what I did is search the official video of Perry's. The video is so hilarious, with the nerd-tastic theme for the fun summer jam Last Friday Night (T.G.I.F.) and it's a doozy. Really funny with some fun cameos by Darren Criss, Kenny G, Kevin McHale, Debbie Gibson,Hanson, Corey Feldman and, of course, Ms. Friday…