Why the Rec anime had to be cut short.

The Rec manga ratchets up the sexual tension as it goes along.  This
may sound like an odd thing to say when the heroine loses her
virginity right at the start, but this event casts a long shadow over
the series.  (Compare with Yui of Fushigi Yuugi.)

The Rec anime only covers the start of the manga, but even in this
"low tension" area it has to change some of the plots to fit under the
rating for the TV slot it aired in.  If it continued it would quickly
run into plots such as the rape scene that would be a jarring change
from the tone it had set so far.

But the anime ends with a carefully crafted conclusion that implies
that the main conflict of the series has been resolved and it does get
across the very important message of the series, which is that all of
the heroine's problems would be solved if she'd just put out more.

This may not sound like an important message in the west, but Japan is
facing a population collapse.

-HJC