Starting off as an isekai romance, Risou no Himo Seikatsu eventually becomes more focused on introducing modern conveniences to fantasy world (this is the first time I’ve seen someone bring a hydroelectric power generator with them across worlds) and political pseudo-drama.
The romance becomes more of a background thing which only comes to the forefront when the topic of concubines is broached. In a manner similar to Arifureta, the protagonist here is staunchly monogamous despite those around him trying to force a harem… only to slowly give in to the outside pressure as time goes on.
The first four books are solely focused on his wife, while the next four introduce and effectively lock in the girl who’ll become his second. Presumably books nine through twelve will continue the theme with the new covergirl but… well, my first impression of her is far from a good one and I’m honestly not looking forward to any amount of focus devoted there.
So I think I’ll wait for that twelfth novel to be released before considering whether to continue any further.