Tensei Shitara Slime Datta Ken (WN) - Chapter 314

One day, Zhang Fan, a poor medical student, receives a medical system from the future. This turns him into a new shining star in the medical field. Along the way, he must face medical corruption, competition, and infighting from other doctors, and even find time for a love life as he strives for the top of the medical field!

- Description from Novelupdates

(Third Person Limited PoV.)Betrayed by his fiancée, mocked by his siblings, and disowned by his family—that was Lev’s fate.Even when he regained memories of his life on Earth, where he realized that his world was strikingly similar to his favorite novel, it still didn’t help him change anything.How could it be?Because the protagonist of the story had already achieved his happy ending—gaining a beautiful wife and living a blissful life. Meanwhile, the world continued to move forward.What do people usually do with a novel that has ended? They tend to stop caring about the world within it, even if it falls into ruin, especially if the novel isn’t particularly popular.The world Lev Razanov lived in shared a similar fate—it was destroyed.[Hero’s System successfully installed.][Critical condition detected.][Do you wish to return to the past?]Lev was given a chance to return to a time when the story of his favorite novel had just begun.Although he was destined to become an extra villain—a pawn of the pawns serving the real villain, he vowed to end the lives of anyone who had caused him suffering: his siblings, his fiancée, the main character, or anyone else.[Hero’s System inherits your desire from your life on Earth—the desire to do good.]“Who said killing your enemies is an evil act?”

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.

“Obtaining the topmost degree of talent in sword arts in the world requires giving up 72 years of lifespan, which leaves you with only five more years of your life. At the same time, you will never be able to feel love, kinship, and friendship, and you’ll end up leading a lonely life until your death, unable to procreate, or to have any descendants.

“From now onwards, everything related to happiness in the human world shall no longer be of your concern. Are you willing to accept this?”

“Hahahaha, I’m already alone bereft of all support, my hopes dashed to pieces, shouldering only absolutely irreconcilable grudge and hatred, why would I disagree? Why would I not want it? I couldn’t ask for anything better!!”

His sword sweeps across the Divine Continent for seven days and nights, moving 90,000 miles through the starry skies, unhindered.

He slays saints and buddhas in Heaven, slaughters demons and devils in Hell, sweeping away all the grievances in his heart!

- Description from Novelupdates