I liked Clockwork Angel better, but on rereading Clockwork Prince recently, I find it growing on me.
Mortmain is the Clockwork Prince. There's a flashback to him and his adoptive father, the warlock John Shade, surrounded by mechanical creations. Shade says to the child, "Look well on this, my son, for one day I shall rule a clockwork kingdom of such beings, and you shall be its prince."
(I didn't take notice of that, either, the first time I read it.)
As for the second trilogy of The Mortal Instruments, I was disappointed in City of Fallen Angels when I read it -- although it did have its moments, it seemed to me that the characters were not as well-drawn. It was the dialogue, I think.
When City of Lost Souls arrived last week, I told myself that if it disappointed, too, I'd not be buying the last book. COLS started slow, and I had just about made up my mind not to continue (about 1/4 through) when she hit her stride, the characters came back to life, the action picked up, and I regained my enthusiasm.
There was too much torrid teen romance for my taste. Some of it was good and drove the plot, but some of it was ... a little too much information for me. At my age, there are certain things you don't want to know. I was willing to put up with it, though, because I liked everything else.
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