If her only reason to develop a crush on him was because he recognised Rirururu, it's pretty safe to say she didn't know much about him beforehand. Maybe not even much about what real anime otaku do in general. She's merely a big fan of a single series, but that's it. Apparently she doesn't watch much anime herself, aside from rewatching Rirururu, so it was shocking for her to see the fanservice in the random show he just received. If this wasn't a romcom, one might wonder how much or long her crush could withstand.