For Sale. Fallen Lady. Never Used. - Chapter 16: Dungeon Nightlife (3)

After rebirth, she, who used to be a top international spy, becomes the eldest daughter of the Fengs, a fat girl who is ugly and foolish in the eyes of the ordinary people.
Mastering Royal 18 Saber Moves and Purgatory 9 Palms, she rose to fame with the martial arts of Demon Cook.
Upon an imperial edict, she was ennobled as the wife of Lord Cen, and then suffered various intrigues and plots…
She proved herself to be a real overmatch and a true genius to the world…

Happiness of the family >>>>>> World peace!? The curtain rises on another fantasy slice-of-life tale, brought to you by the “Hataraku Maou-sama!” team.

On that day, an emergency family meeting was called to order at the residence of the Kenzaki family, an ordinary family living in Tokorozawa City. A blonde beauty named Dianaze Krone, Diana for short, had appeared from a different world, in the living room of the Kenzaki family. “I, an envoy, have come to summon the Hero of Salvation, Kenzaki Hideo.”

Wait, Hideo is my dad! To think such a game-like situation would fall upon me, Kenzaki Yasuo, an ordinary high school student.

My father is a hero, and he saved a different world in his younger days!? There’s no way I can believe that this ordinary, middle-aged father of mine is a “Hero.” Diana looks at me, “The Son of the Hero” with a gaze filled with longing. My sister who saw that looks at me with a cold gaze… Before bringing back peace to the other world, the peace of our family is in big trouble! What is going to happen to my peaceful everyday life!?

“Mr. Qi Lin, may I ask how you thought about joining the entertainment circle from a sports student?”

“Uh, I said that I was there to deliver lunch boxes, do you believe me?”

- Description from novelbuddy

In a Fantasy world in which a young girl with the Divine Protection of the Hero battles against the Demon Lord. In that world, Red, the elder brother of that young girl Hero, possessing the Divine Protection of the Guide which only grants a high initial level, fought in the initial party of the Hero.