You can just read about them instead of actually reading or watching the entire series. I know a bit about Ah My Goddess, but haven't actually watched any of it.
Incidentally, I recently plowed through the entire Eva TV series, watching one DVD a night, on six non-consecutive nights, and just finished watching End of Evangelion now.
As for the sheer quantity of references, I could probably duplicate them myself by looking through my book collection... by the time I finished high school, I had enough paperback novels to fill several bookshelves.
So I'd intended this story as a bit of utterly deranged fun, but it got out of control and ended up as a deep philosophical exploration, and now those of you who care will have to wade through the insanity. I'm sorry. I just can't seem to help myself.
I know that writing crossover fanfiction is considered one of the lower levels to which an author can sink. Alas, I've always been a sucker for audacity, and I am the sort of person who couldn't resist trying to top the entire... but never mind, you can see for yourself.
Click on to read my latest story and first fanfiction, a Vernor Vinge x Greg Egan crackfic.