Note: This story was dynamically reformatted for online reading convenience.
 
 I'm a big fan of the Swarm cycle by Thinking Horndog, and always wanted to
see a fantasy equivelent.  The Succubus invasion is set in the near future
when a massive spell finally failed, allowing the Succubi to return (along
with other magical creatures).  The spell had drained all magic to power
itself, so when it went down magic returned as well.  Succubi are capable
to taking over any man, and most women, who are not sexually sated, so the
only defense against them is rampant sexual activity.  Of course, magic can
cure all STD's and prevent unwanted pregnancies, so it isn't such a big
deal any more.  The Succubi quickly took over about half of the earth, but
humans fought fiercely for the other half.  Unedited for now, sorry,
haven't been able to find a good editor.