I find it fascinating that this is in the Shoujo genre because I find it much more Seinen personally. Regardless, if you're into the Yandere character type, this is a must read. I read a metric ton of this genre (mostly books), but this manga is a standout because the male lead is actually very interested in the female lead's consent. If you engage in Yandere, you'll know the lack of consent is a common trope, and, while I have nothing against that, seeing the male lead so invested in her consent over her domination is very refreshing.
Satoko is sometimes naive because of her sheltered upbringing, but she grows from her mistakes and, most importantly to me, always makes a point to be useful where she can. Sure, she can't do much against 10 assassins all after her head, but she can outsmart the conniving nobles and courtesans who would plot against her.
Shinpei is a force of nature, stronger than any other swordsman, but he wants to know love in his own way, strives to work with Satoko and talk through things, and I find them both very refreshing as leads.
I look forward to where this story will go since we're only 26 chapters in, but there hasn't been a single miss yet.
Edit: after seeing the manga in Japanese, I think it's Seinen after all. There are no furigana on the kanji, so it's definitely intended for an adult audience. As a heads up, there's violence, nudity, some sexual stuff, and so on, but no gore (e.g. viscera) or explicit sex yet, so genre could definitely go either way.