Sexual Slavery and Islam
This is very a disturbing inside view, written by a Muslim convert for a Muslim publication: Traditionalist View on Sex Slaves.

Here's an excerpt:

Years ago, when I first learned about Islam, one point that bothered me was that Islam appears to tolerate slavery, at least according to traditional opinion. My Muslim friends responded to my concern with the usual traditional apologetic logic: They said, Islam tolerated slavery only to avoid a social and economic collapse and therefore made slavery vanish not suddenly but slowly over time. When I heard this the first time, I assumed slavery disappeared in the course of a few generations. Several years after I became Muslim I was shocked when I learned that in fact, slavery lasted on for more than a thousand years, until the nineteenth century, when international agreements between Muslim and Western countries banned slavery, and it clearly seems the Western countries were the driving force behind this move.

But there was something even more shocking: According to traditional schools of thought, not only was slavery permitted, but they also approved that every male master had the right to force any of his female slaves to have sex with him. This fact not only shatters any illusion one might have about the dignity a slave enjoyed according to traditional schools, it also smashes any hope to find a social or economical rationale for it. To me, this became a prime example for the necessity to reconsider the traditional rulings. I thought that any reasonable person would agree that the case of slavery and sex with slaves showed clearly that the traditional schools could not be relevant for us without major revision. Unfortunately, I had to learn that traditionalists do not agree.