Explore the world, one post at a time
One of the most obvious arguments in favor of a romantic relationship between Achilles and Patroclus is simply that it makes sense from a writers perspective. Want to absolutely destroy your main character? Bring them to their breaking point? Punch your reader in the gut? Kill the love interest.
I mean, come on, the greeks were the inventors of the tragedy for a reason. What's more tragic? The death of cousin/comrade or the death of the person you are irrevocably and maddly in love with?