On <3 I was trying for a mathematical interpretation and well puzzled. Thanks folks.
@TitaniumTi - that's a very good point on the covers.
I've read all of St Mary's - in fact galloped through them once I'd learnt of their existence (which was well into the series). I am certainly entertained by Max, thought about whether she is likeable and decided that on the whole I like her. Not the easiest person to be around (another one like Miles Vorkosigan) but I like mouthy, independent folks, I like eccentric researchers, so all fine by me. Now wondering how everyone defines likeable.
In fact nearly all the characters in St Mary's the academic college itself strike me as plausible academics/re-enactors of the determined, energetic, obsessive kind who don't even consider what the rest of the world thinks of them.
The St Mary's covers changed part way through the series, but they've retained a theme of darkish colours, historical scene and something indicating time. No individual portraits at all.
Trying to remember how soon the romance side of the series starts - as in Max's relationship. Once it is underway, there are energetic sex scenes including one on the bonnet of the boss's Bentley. (Not with the boss). As far as I can remember, not a super-detailed scene, but definitely not fade out as they start to kiss. But there is no hint of that on the covers. It is much more a relationship than a classic romance and extends through the series in a sometimes stormy way.
Some of the covers are here:
https://www.accentpress.co.uk/the-chronicles-of-st-marys-series
I was under the impression that Accent Press liked some romance in all their stories, but they don't currently have submission guidelines up, so can't say that for sure. (For calibration). They have Jodi Taylor marketed as historical fiction and humour even though it centred on an institute that investigates historical events by travelling there in a time machine. They have one book categorised as science fiction and none as fantasy. So there you go, I'd have put St Mary's into genre, they don't.