I'm currently at page 172 or RTTW. I saw a reference to Hyacinth and Kypris that stirred these thoughts to the surface but no spoilers for RTTW in this posting. There SPOILERS for OBW and IGJ.
I've had this question on the tip of my tongue or the back of my brain off and on since I finished the last Long Sun book a few years back.
Silk and Hyacinth.
I can understand Silk's attraction to Hy. She is the beautiful (movie star/pin up girl/prostitute) that many a young man develops a crush on. She is his "Picture of Lily." But as the father says to the son in that Who song, "Son now don't be silly."
You do not try to obtain someone like that for many reasons. First obtaining them is very difficult for the average man. But Silk is way above average so he does manage to obtain her for a time. But once obtained even for men "on their level" you can not keep them. Look at movie star divorce rates, etc.
On Hy's part. I can see her being attracted to Silk for many reasons.
-His unnatural leadership charisma (genetically modified embryo)
-His ability to help her escape a situation she has grown tired of
-Kypris manipulation of her
What I can not see (without Kypris modifying Hy's will) is her staying with Silk for many years. I believe that when she ran away from Silk instead of boarding the lander, that she was not just afraid of a hard life on Green/Blue, but that the newness of Silk had expired and she was looking for an excuse to ditch him. I did not expect him to find her again. Or at least not to be able to convince her to stay with him.
I see Silk and Hy after the end of Exile as the relationship of Hosea and Gomer of the Old Testament Bible. Hosea constantly had to go to the marketplace and drag Gomer back home to keep her from sleeping with other men.
What are your theories on their relationship, since Silk and Hy seem to have been together when Horn enters Silk's body in IGJ. Did Kypris put a compulsion on Hy to stay with Silk? Or have I misjudged her?
Dennis/Endy
http://home.mindspring.com/~endymion9/index.htm
*This is WHORL, for discussion of Gene Wolfe's Book of the Long Sun.