Eldritch Creature's Guide - Chapter 276 Juulius Vs Bagtork

A college student, accidentally reborn into the world of Naruto, becomes a member of Uchiha who is destined to be exterminated.

In this cruel ninja world, in the face of endless wars and exclusion from the village, what will Uchiha Qing do?

PS: Later in the book, the protagonist will develop a system of immortal cultivation. Cultivating Immortals in the Ninja World, have you seen it?

- Description from novelbuddy

Transmigrated to become a disciple of the demon sect, relying on the technique modifier to become a giant of the demon path.

[Detected the technique “Blood Nerve”, relying on devouring blood to cultivate]

[Side effect: easily affected by the spirit contained in the blood, becoming bloodthirsty, murderous, insane, and even brain dead]

[Please wait, system modification is in progress…]

[Ding! Modification completed and side effects canceled]

500 years ago, Chen Xi was devoured by a crack in the void and was transported into a cultivation world.

500 years later, he returned back to Earth after enduring through several hardships and discovered that only 5 years had gone by.

…

In the courtyard, beauty at the side, a candle flame wavering.

A gush of clear wind, half a full moon, the peach tree remains unchanging.

…

Wait, whose kid is this?! Why is she calling me papa? Gazing at the little girl in front of him with skin as pale as jade, Chen Xi froze.

…

　
Returning home from cultivation, starting as a stay-at-home dad.

In this life, not fighting to be a king nor claiming to be a tyrant, only praying to peacefully be a wife-pampering mad devil and a child-protecting daddy!

- Description from Novelupdates

I’m in a secret, bad romance with a love dependent student—「Having a secret meeting with a student one is in charge of at school… Isn’t it exciting?」The special relationship with Kirihara that no one can know about began when I took up my post at Mori Kawara High School as a teacher.At school, she’s the serious student council president who has earned a lot of trust from other teachers, but when it’s just the two of us, she becomes mischievous, clingy, and jealous.On weekends, I cook meals at her place, play games together, and pamper her as if we were lovers.Unable to reject her because she knows my weakness, and despite knowing it’s wrong, we continue to pile up secrets little by little every day…「Sensei, my feelings of liking you have grown very strong.」As Kirihara openly confronts me with her feelings, the emotions I’ve been holding back grow even stronger.Even though it would all be over if it were exposed, that sense of immorality ironically only accelerates things further—