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Isekai Ooku - If you want to be a queen, you must continue to be loved by His Highness at night!

Only a woman who bears the prince's child can become queen.
Reina was stabbed to death by the groom during the wedding ceremony, and when she lost her life, she found herself reborn in a different world.
There, she finds herself in the inner sanctum of the royal palace.
She discovers that she is a candidate for queen, gathered for the princes.
The strong-willed Reyna is noticed by the mean-spirited seniors and is forced to perform a new dance (naked dance).
However, the prince, intrigued by Reina's refusal to be bullied, invites her to a night dance....
As she is sweetly embraced by the prince and feels the pleasure of being a woman, her desire to become queen grows even stronger...

English Webtoon version (Ongoing): https://comiko.net/series/82238/isekai-ooku-ohi-ni-naritakuba-yotogi-de-denka-ni-aisaretsuzuke-yo-official