Oshiete! Galko-chan, Hajimete no Gal Recommendations
1) There's gyarus in it!
2) Both gyarus betray the sterotype of being a 'gyaru' in some way or form
3) There is an otaku-like protagonist (though Hajimete no Gal's is a male and Oshiete! Galko-chan's is a girl)
4) Both very enjoyable series!