I am looking for manga where the main character is a concubine in a harem. A real harem, like in ancient times. A strong, exceptional woman. Ones I've read:

Yume no Shizuku, Ougon no Torikago
Crazy Girl Shin Bia
Red River
Pearl Grudge
Scarlet Palace

Try:
Sabaku no Harem
Saiunkoku Monogatari
Ookami Heika no Hanayome - only MC in the harem, but still has some of the intrigue
Koukyuu Days - Shichi Kuni Monogatari - MC isn't actually a concubine

Thanks for the suggests 🙂