Anyway....

Evilminion is totally right, for the most part 
the girl characters mentioned are the *main* 
characters of their series.  They also seem to 
have a lot more thought go into their design.  
Belldandy's character design is gorgeous!  
Keiichi (?) looks well...like a whole lot of 
other anime high school guys.  By the same 
token, characters like Wolfie and Vicious are 
cool and *very* pleasing to look at (prettier 
than the women in the series' anyway.  I *hate* 
Millie and Meryl) plus they have the added 
bounus of being quite rare in that they don't 
appear in the bulk of the episodes in their 
respective series.  The same could be said for 
Deedlit and Pirotess (especially)-they don't get 
as much screen time as Parn.  But Ashram can 
cost just as much as either of the ladies!
Sesshoumaru will almost always cost more than 
Kagome (no big shock) and Sango.  

Really, it *does* usually seem to come down to 
how downright cool the character is.  

It doesn't hurt that the female characters have 
boobs I'm sure ^_~  Lets face it, women may be 
in the majority here on the cels forum but most 
of the big anime fans out there are guys.

But God help anyone who gets in between me and a 
shirtless Wolfwood!