Muhammad beheads 600-900 men and takes Rayhana as a sex slave (Banu Qurayza)

Muhammad ordered the beheading of 600-900 men of the Jewish Banu Qurayza tribe and took their women and children as captives. Muhammad also took Rayhana, one of the captive women, for himself.

Here is the story from authentic hadiths, Muhammad's earliest biography, and the Quran:

"Sa'd said, 'I give the judgment that their warriors should be killed and their children and women should be taken as prisoners.' The Prophet then remarked, 'O Sa'd! You have judged amongst them with (or similar to) the judgment of the King Allah.'"
Sahih Bukhari 3043

"I was among the captives of Banu Qurayzah. They (the Companions) examined us, and those who had begun to grow hair (pubes) were killed, and those who had not were not killed. I was among those who had not grown hair."
Sunan Abi Dawud 4404

"Then the apostle went out to the market of Medina (which is still its market today) and dug trenches in it. Then he sent for them and struck off their heads in those trenches as they were brought out to him in batches ... There were 600 or 700 in all, though some put the figure as high as 800 or 900."
Ibn Ishaq, Sirat Rasul Allah, p. 464

"The apostle had chosen one of their women for himself, Rayhana … and she remained with him until she died, in his power. She had shown repugnance towards Islam when she was captured and clung to Judaism."
Ibn Ishaq, Sirat Rasul Allah, p. 466

"And He brought down those who supported them among the People of the Scripture from their fortresses and cast terror into their hearts [so that] a party [i.e., their men] you killed, and you took captive a party [i.e., the women and children]. And He caused you to inherit their land, their homes, and their properties."
Quran 33:26-27

I've posted this argument along with others on this website (with linked sources): https://islamsproblemabc.github.io/islam-problems/