A. J. Demas’ 2018 One Night in Boukos is a standalone novel that shares a setting with the author’s Sword Dance secondary universe series.
The Pseuchaian city Boukos is home to a thousand brothels. Small wonder that the town hosts the Psobion festival, which offers participants the opportunity for extensive debauchery. The festival is a new and alarming thing to most of the Zashian embassy … but not to the ambassador, his Excellency Zukohashkra. He’s in town to negotiate a trade deal between Boukos and Zash and intends to take full advantage of barbarian delights.
The slave eunuch Bedar accompanies Zukohashkra to a party but finding it not to his taste, returns alone to the embassy quarters. He assumes that Zukohashkra can find his own way home.
Zukohashkra does not.
It takes Bedar and Marzana, the captain of the embassy guard, some time to realize that the ambassador has not returned to his official residence. Once they grasp this alarming reality, they have a choice: raise a public hue and cry, which might embarrass the ambassador, or go out themselves to look for Zukohashkra.
Bedar and Marzana are quite sure they are up to the task. True, Boukos is an unfamiliar barbarian city. The investigators don’t know the streets and regard Pseuchaian customs as bizarre and alarming. But that shouldn’t matter … right?
Bedar and Marzana have shown themselves to be diligent and thorough. In the past. In this case they both prove surprisingly distractable. Bedar follows the ambassador’s trail to a brothel specializing in boys, where he meets the slave prostitute Pheres. Marzana for his part encounters the attractive widow Chereia. Both Zashians are smitten and momentarily set aside investigation for flirtation.
Meanwhile, the ambassador is still missing. In fact, the ambassador has been the victim of a kidnap attempt by anti-Zashian fanatics, although for reasons his subordinates only belatedly realize, the ambassador is under the impression that his would-be kidnappers are simply extremely friendly locals. Whatever impression the kidnappers have given Zukohashkra, he is in mortal danger and in dire need of rescue.
Zash is Classical Persia, more or less, while Pseuchaian cities like Boukos correspond more or less to Classical Greece. Each regards the other as barbarian. Both have practices the other finds distasteful. Neither one has values even remotely like modern values, which is why Bedar isn’t particularly upset about being a eunuch (which allowed him to become a very highly placed slave of a very important man) and why he spends most of the book chasing a sixteen-year-old boy.
I must admit that I found the whole “Bedar falls for an enslaved minor sex worker” sub-plot pretty off-putting. Granted, Bedar is only three years older than Pheres. Granted, in their cultures, everyone practices slavery and people get married at sixteen. But I’m not from their cultures.
Readers may wonder how it is the two Zashians allow themselves to go so far off mission mid-book. Lamentably, the ambassador is the sort of well-connected, self-indulgent nincompoop whom subordinates are unlikely to miss, save for the bother that would follow if they had to explain how they misplaced the Emperor’s kinsman. It’s a strong argument for selecting functionaries with merit-based tests, perhaps about the minutiae of literature.
Despite the life-and-death stakes for which the characters are unwittingly playing and the occasional moments of bloodshed  that occur, the tone remains for the most part comic, preferring to focus on the wacky adventures and unexpected romances that befall the two leads rather than the political extremism and violent purposes with which other, less fortunate characters concern themselves. Readers looking for light distraction may enjoy this.
1: A moment of silence for two palanquin bearers who were in the wrong place at the wrong time.