Narika: The Ghost Bride - Chapter 200 - Two Hundred:His Queen.

Step 1: Inherit a creepy old mansion.Step 2: Unlock a cursed system that makes girls fall dangerously in love with you… just by saying “hi.”Step 3: Learn that if you don’t reject them within 10 texts, something terrible happens.My name’s Ren.And apparently, I’m the “Catalyst for Affection-Based Catastrophes.”(Yeah. That’s literally what it said.)My peaceful new life? Over.Now I’m stuck in a house full of magically unstable girls:A sword-swinging elf.A fire mage with zero personal boundaries.A strict class rep who faints if I so much as look at her.And a witch who cursed the bathroom mirror to spy on me.They’re beautiful.They’re powerful.They’re dangerously obsessed.And if I mess this up, someone’s going to get hurt—maybe me.Reject them too late? Game over.Fall for one of them? Even worse.This isn’t a dating sim.It’s survival of the cutest.Welcome to my life. It's not just a harem. It's a hostage situation.

Travel to the primitive world, open up wasteland and farm land, tame animals and fish, build houses…

Jiang Xuan wants to create a tribe of his own!

- Description from novelbuddy

Anyone who could construct a stable Spell Model could become a Wizard — that was the Wizards’ ultimate secret! Having been given a new life as the son of an aristocrat and armed with a super quantum computer from his past life, Spell Models came as easily as breathing to Merlin. With this overwhelmingly huge advantage, would Merlin become the greatest Grand Wizard of all time?

- Description from Novelupdates