The Hero King, Reincarnate to Master the Art of War ~And Thus, I Became The Strongest Knight Disciple (♀) in The World~ - Chapter 29: 15 year old Inglis, Departure to the Royal Capital

In a world ruled by strength and chaos, a soul from modern Earth awakens in the frail body of a seven-year-old Sakazuki. Orphaned by pirates and left with nothing but a burning hatred, he refuses to remain weak. With knowledge from his past life and the power of the Magma Magma Fruit, he begins his ruthless ascent through the ranks of the Marines.But justice is not so simple. Corruption festers within the very institution meant to uphold order, and the line between protector and tyrant blurs with every battle. Undeterred, Sakazuki will forge his own path—one paved with fire and blood.From a vengeful child to the most feared force in the Marines, witness the rise of a man who will set the seas ablaze and redefine what it means to bring order to a chaotic world.

His Royal Highness the King of Han, who was afraid of the dark and ghosts and loved to cry, has always been the good baby of the princess.
Until one day, His Royal Highness the King of Han found a book in the bookstore…
Picture book?
Content tags:
Search keyword: Protagonist: King of Han, Princess of Han

- Description from novelbuddy

I, Lin Yun, with my exceptional aptitude, had thought that I would be trained as a key disciple, however...“The Demon Sect will never expect us to send such an excellent disciple undercover. Once you attain a high position within the Demon Sect, with our help both from within and without, why would we worry about the Demon Sect's destruction?”Three years later.“The Righteous Path will never expect us to send such a promising disciple undercover. Once you attain a high position within the Righteous Path, with our help both from within and without, why would we worry about the Righteous Path's destruction?”Lin Yun: I just want to quietly cultivate to immortality...

Nijigen is a freshman and Banri’s friend. He gains his nickname at the tea ceremony club’s welcoming party after declaring his despair of the three-dimensional world and that he would live for the two-dimensional world from then on. His nickname in high school was “Satoutaka”.