I think the part of the 40k fandom who really earnestly want to prove Astartes do/can in fact fuck are kinda missing the point.
Like Astartes are at their core deeply tragic creatures. They're people who've been turned into tools to serve the interests of fascist imperialism and, in the process, have had their humanity stripped away because they're purely utilitarian by design.
The scope of their entire existence has been narrowed down to a single point. They're more advanced than baseline humans in a physiological sense--stronger, faster, larger, better reflexes, etc--but beyond that, they're actually more limited.
There's a point in one of the Night Lord books where Octavia observes that, for all of the Astartes' advanced capabilities, they're really quite developmentally stunted. Like, huge powerhouses with unnaturally long lifespans, but the hyper-simplistic emotional depth and worldview of a 12 year old.
Which adds up. The Astartes love to sneeringly dismiss things like sexuality, intimacy and romantic love as nothing but the base, inferior drives of mortals, but once you strip back the superiority complex, it just sounds like a tween boy who can't wrap their head around why anyone would want to kiss a girl.
And, again, it's all by design; the Imperium doesn't want them developing attachments outside of a basic sense of brotherhood and filial love for their Primarch because that distracts them from their sole intended purpose. You don't want your hammer vanishing on a fuck fueled vacation to Bali with your handsaw when you're trying to build a shed. It's all a means of control.
And I get finding one of them hot and having horny headcanon, go fuckin nuts.
But whenever I see a reddit post that's like "B-BUT THE SPACE WOLVES FUCK! HORNY ASTARTES ARE CANON--!", it's like...I dunno, isn't it more compelling if they can't? That they've been robbed of simple human joys in order to better serve the interests of an uncaring theocratic fascist state? And they can't even grasp what's been taken from them?
Maybe that's just me.















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