Not for the young or faint of heart.
A Song of Ice and Fire are a dark fantasy series by George R.R. Martin, originally intended to be a trilogy, now destined to be a septology alongside three Expanded Universe novels which are more friendly of format (that is the actual size of the books) and currently awaiting the arrival of the fifth instalment since 2004.
The series are famous for their rather gritty perspective on a fantasy world, which is often more like some Mad Middle Ages than your average unicorny fantasy and due to that also slightly less realistic than those (how incredible it may sound), unless you are of the "ultimate cynicism equates realism" kind (though the events aren't that unrealistic, to be fair; the frequency is, though).
Regardless of that, the author manages to make it look way more credible than it actually is and has a very effective writing style. The series are written from the perspective of several characters [understatement], with also death occurring to those.
Basically, the story is about the kingdom of Westeros fifteen years after the murder of the previous king and the crown prince by several usurpers who of course has their reasons. I'm rather iffy on spoiling too much but the sheer length of the series should indicate that quite a few bad things happen. If you want you could check it on TV Tropes, but they actually spoil quite a lot outside the spoiler tags, so check it at your own risk!
As I said these series are rather dark and not really suitable for younger audiences. So please, do not read these books nor enter this discussion if you can't handle it. For instance, mature themes exploited include
(mass) rape, torture, extremely deaths, major paedophilia, human sacrifice, infant killing, incest and treason (which may sound petty, but it is really stomach-turning at times). So, yes, unless you think you're up to cope with that, please stay away from this topic.
I'd personally like to discuss quite a few things about the books with others who have read it, though please take care to use [spoiler] tags rather abundantly. I really do not want to spoil people's fun reading and I will ask you to use spoiler tags if you failed to do so.
Another thing to mention is that there has past quite some time after I read the books and that I read it in Dutch, so don't be surprised if I don't really get what character you refer to, even if you use the right name and all.