The Real Rich Daughter is a Future Genius Scientist - Chapter 1: Rebirth

Only a pure maiden can have a privilege to make contract with a spirit.

In Areishia Acadamy, maidens from noble family were gathered there, giving them an elite education to become a spirit contractor. A boy Kamito, by accident he peeped on a girl, Clair, who was taking a bath, and he even made a contract with spirit that she wanted.

Kamito was actually an irregular male spirit contractor, which should not exist.

“Welcome to the Punishment Zone, scums.”

“Please tear the masks of pseudo-gods into pieces here.”

“However, you must remember—the time for slaughter takes place only after sunset.”

- Description from Novelupdates

When The Cute Kunoichis Spied on Their Teacher's Secret is a light novel written by Kazuma Kamachi and illustrated by Ryuushi Tajima.

The story takes place in a world where Japan never ended their isolationist phase, and agents from foreign powers are always threatening to steal the country's advanced technology. In order to combat this threat there has been a resurgence of ninjas that use Strategic Martial Arts, techniques that combine cutting-edge modern technology with a traditional foundation of martial arts and ninjutsu. The story follows Souha Sugiyado, a 17-year old ninja instructor and former ninja prodigy who was forced to retire from active duty by the wounds he suffered in his last mission. Souha's four students are all kunoichi who have all gained the rank of Elite Ninja, the highest official rank available to ninja. However, one day two Shogunate ninja approach him with the news that his four students have gone rogue and have stolen a portable modular nuclear reactor, and thus they ask for his help in bringing his students to justice.

A lonely soul, which was placed under the care of the Lord Protector’s Manor, ended up having her lover stolen by the family’s eldest daughter and dying tragically the day before her wedding.

Somehow, she was reborn in the family as their 14-year-old first wife’s daughter, Ning Xueyan, with a startlingly familiar face.

Step by step, she will ruthlessly scheme to seek revenge as well as uncover the mystery of her tragic death.

Her former fiancee, the flirty crown prince and the bloodthirsty prince, will now bear witness to a vengeful Ning Xueyan becoming the peerless lady of her generation…

- Description from Novelupdates