These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Cargo Ship: Yomiko does not just love books, she loves books, and there are times when it looks like she might be crossing a line. It is quite literally in canon: Joker commented, that the experience gained by her from "immersing herself into the book" is "quite similar to sexual ecstasy".
Also have Nenene and Maggie (if one considers Maggie's flustered reaction to Nenene's threat to kiss her), Anita and Hisami and Yomiko and Nancy.
Moe: Yomiko, big time. Hisami is often seen as this, too.
Suspiciously Similar Song: One of the tracks in the OAV, "Those who insanely love books say, 'Paper is always with us'" sounds strikingly similar to "Valse Aux-Champs Elysses", a stock music track from the APM library.
Woolseyism: The dub of the OVA added a lot of clever lines, mostly relating to Nancy's dialogue.