This is a novelization/memoir style telling of the Epic of Gilgamesh that's totally NOT GAY.
I have not read/studied the Epic of Gilgamesh, so I don't know how well the story would roll with academics who know such things intimately, and I'm generally going to miss any subtext of what was going on or what constituted pop-culture in ancient Mesopotamia, but overall, it is hitting most of the major plot points I remember. In this story, first person told by Gilgamesh, he's the most amazing, awesomest, strongest, sexiest thing ever, and of course everything is about him. While I get that he's a hero of old, the whole thing just feels like a petulant boy stomping about, even when he's older.
The story isn't super consistent, main example: the initial driving force for Gilgamesh is that Inanna, or the priestess of Inanna, is the great love of his life, who he spends a good portion of the book freaking out about, because she's having ritual sexy times with Dumuzi the king, but then he treats her like utter shit for no particular reason (the idea of a conspiracy between her and the King of Kish is punted about, but doesn't seem to be a driving force between the two or really mentioned much in his reasoning).
Anyhoodle, he rants and raves around, for a good part of the book, until we get to the bit with Enkidu, which Gilgamesh tells us is DEFINITELY NOT GAY so many times, you can't help but get the homophobia present in the book. He'll mention it several times later on, and he even doubles-down on the homophobia (initially) by bringing up homosexuality and then mentioning that homosexual relationships are less than heterosexual ones... Keep bringing it, Silverberg).
So this story is generally the Epic of Gilgamesh, with Silverberg filling in to give him a more fleshed out childhood and then ordering everything in such a way that it seems to make sense, gods and all. And totally NOT GAY. But for all of that, it's a dry and stilted tale; whether this is intentional or just shoddy writing, I'm not entirely sure, but I didn't enjoy it.
I'm not the biggest fan of Silverberg (I have many friends/acquaintances that are, which is why I'll pick his stuff up on sale like I did this work), but I was really disappointed in this novel.
And then to make matters worse - I listened to the audiobook, so I'll review the reader because I think it's more important in this book than some of the others:
The narrator is AWFUL (William Coon). He drags out vowels and certain syllables in a way I can't get (as in, I don't understand the choice to do so). He has an American accent, but I haven't run into a regional thing where people do this, and his voice is so atonal, it feels like I'm listening to BirdPerson from Rick and Morty telling the tale. I spent more time than I'd like to admit, paying attention to the book to see if I didn't like the book/story or I didn't like the narrator. Maybe (probably not) this style of narrating would work for an actual epic poem, but not here. It's a rare, terrible narrator that is so absolutely bad that I'm not sure he's not making me dislike the book more than I already do. If you speed the narration up to 1.3x regular reading, you start to approach a more normal pacing, though the tonality doesn't improve.