Death March kara Hajimaru Isekai Kyusoukyoku (WN) - Book 2 - 2-3. The Chant, the Soldier and the Noisy Afternoon

Legend has it that the world’s most formidable man Xu Shuangtze owned a cherished portrait of his deceased wife. But no one knew that on its back was another portrait of his arch rival who Xu Shuangtze had killed with his own hands.

Sixteen years ago, the Chief of Immortal Alliance’s Department of Discipline, Gong Wei, brought a blade with him on the Immortal Ascension Platform. His assassination of Xu Shuangtze failed and he was slain on the spot by the sword named No Way Out.

Sixteen years later, Gong Wei opened his eyes and found himself reborn in the body of a beautiful fool who even had to kneel down when talking to Lord Xu.

This was not the only disturbing thing for him.

Because of his ravishing good looks, remarkable power and status as well as his premature death in his previous life, he was now the beloved muse of countless writers. Books and stories featuring him as the main lead to all kinds of relationships were circulated far and wide. Even among the famous sects there were rumours of his forbidden encounters with every sect leader…

- Description from Novelupdates

A martial art expert from the Song dynasty lives like a Phoenix that can live again in another body after death. This time, he happened to take over the body of a Japanese high schooler who is also a victim of bullying and has a bit complicated family circumstances.

Xu Ping'an was overjoyed to marry, but what welcomed him was a deception.Eight years of devotion, eight years of infatuation, only to be repaid by the one he loved plucking his spine and devouring his bloodline.“You take my spine, I'll turn my Thunder Sword into bone, defy the heavens to change my fate, and awaken the memories of the Immortal Emperor from a past life.”In this life, I will make all those who betrayed me descend into Hell!

“Married rich for three years with no child born. Just when she was finally cured of infertility and ready to give him a child, he brought home his pregnant mistress in high profile.