Dousei kara Hajimaru Otaku Kanojo no Tsukurikata

If I'm going to find a girlfriend, she has to be an otaku. She'll be beautiful, innocent, with long black hair, and she'll like all the stuff that I like! Kokoro Nishina, the girl I'm living with, is the exact opposite of that. So why did I promise that I'd turn that flashy, extroverted gyaru into the ideal otaku girlfriend?! Sadly, I know just how it feels to need a little self-improvement to find the perfect date... and there's no way a girl like that will tell her friends that she's actually a closet fujoshi. But I'll teach her—then maybe she can teach me too! With my expertise, she'll definitely become an otaku's dream girl!

(Source: J-Novel Club)