The Unsullied from Game of Thrones we know were castrated as infants. The purpose is to enhance their battle skills by eliminating all sexual drives as a result of the lack of testosterone production.
In the scene in S7 where Greyworm pleasures Missandei it would appear that he still is capable of having erotic feelings towards women. Can anyone explain?
You did see what Missandei looked like naked, right? That pretty much took care of my suspension of disbelief. Smart casting on the part of the show, in that regard ("she's gotta be beautiful/hot enough to arouse a eunuch...")
A less joking take is that Greyworm formed an emotional attachment to her, more than lust, and their actions was more an expression of that deep, emotional caring that he has for her, more than physical desire. Hence his explanation to her about how he fears (not being able to see her if he should die) for the first time.
Pre-pubescent children, for example, form crushes or strong feelings that are not based on lust, but their emotions and feelings, so attraction doesn't have to be primarily sexual.
The actions in bed were from his desire to please her and express his feelings for her in a way that forms a more intimate, complete bond between them. This is kind of like how in actual marriages where one partner becomes impotent or loses arousal or desire, they still have relations, because it's not just a physical act but one of shared emotional intimacy and vulnerability. Plus being able to please her in that way, since she's not devoid of those feelings, can be satisfying in its own right. That's also pretty ground-breaking and unheard of for the Unsullied, but it at least doesn't defy what we know about human biology and medical science.
ED in Marriage: Keeping Your Sex Life Alive Despite Sexual Dysfunction
I created an account here just to answer this.
I too had this thought and did lots of research. In short Yes, eunuchs can be sexually active similarly to a unaltered male.
Here's a whole article about that scene, including an interview with a medical expert:
"Romantic and sexual urges are complex neurobiological phenomena that have multiple components," Dr. Peter Stahl, the Director of Male Reproductive and Sexual Medicine at Columbia University told us. "Feelings of sexual intimacy in men come from more than just their testicles — personal connectedness, trust, affection, admiration, physical closeness, and cognitive conceptions of sex are all important."
http://www.mtv.com/news/1836500/game-of-thrones-grey-worm-missandei-sex-eunuch/
Another article: http://goaskalice.columbia.edu/answered-questions/castration-effects
There's a lot of good links on Google search on this topic.
