story identification - Pleasure bots as population control

I'm looking for the name of a science-fiction novel/series, which I read sometime between 2001-2005. The only things I can definitely remember:

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  There are "pleasure bots" (there's a name for them in the book, but I forget), actually very life-like, that are stored in some sort of case when not in use. (Sort of like the ivory dittos from "Kiln People", but these are more-or-less autonomous, if a bit empty-headed.)

  
  


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  No one is really sure where these androids came from, but at some point in the book (or later in the series) it is revealed that they were created by a woman scientist-type (who might have been the protagonist in an earlier book in the series) for the purpose of population control, and to reduce violence against women.

  
  
  


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  I think the woman scientist is near-immortal, or can time-travel; unless I'm getting different works mixed up, this pleasure-bot scheme is one of several interventions she performs across centuries, if not millenia.

  
  

Answer

This could be The Companions, published in 2003 by Sheri S. Tepper. The pleasure bots, called 'concs,' short for concubines, are hermaphroditic, small, and beautiful. They are also actually plants, and they were introduced mysteriously onto an overpopulated Earth for the unstated purpose of population control and to give people an outlet for anything from simple loneliness to deviant/violent tendencies. When not in use they are stored in small compartments as you remember. They are described as somewhat empty headed, though they are intelligent enough to adapt themselves to specific owners' preferences. The protagonist's brother Paul, a narcissist and sadist, periodically 'uses up' concs by treating them abusively.

The plot is rather complex and I will not try to summarize it here; however, there is a form of time travel (time pockets that allow time to pass more quickly/slowly), a planet, Moss, that is a collective consciousness communicating by scent; and the primary narrator, Jewel Delis, who helps run a breeding program for advanced, intelligent canines that bear alien DNA. There are several female protagonists, and one of them, a nonhuman sage, is responsible for introducing the concs to Earth.