Cerulean Lotus [Kimetsu no Yaiba]

[Book 4 of 4] Setsuko Mizuki, the last of the Shinobi clan, Mizuki, was found on the brink or death by the loving Uzui wives and raised by the loving family into a flamboyant young woman. Now, five years later after passing the final selection, she's sent on a joint mission with Flame Hashira, Rengoku Kyojuro to test her in the field, after which she is then introduced to his younger brother Rengoku Senjuro. The two quickly become friends and soon are very close. Even though Senjuro is sure he's got no luck with a sword, Setsuko is determined to prove him wrong and show him that with a little practice... and a lot of love.... anything is possible!