MTL - Ghoul’s Infinite Journey - v2 Chapter 20 Dance! Crazy Lan! (superior)

“Look, boss, that red dragon lacks dragon's might, and it doesn't even know how to breathe fire. Let's take it down and make a fortune,” said one of the adventurers.At that moment, the lethargic red dragon opened its eyes, looked at the adventurers appearing before it, drew a forty-meter sword, and deployed techniques such as Sword Mastery, Samadhi True Fire, Eighty Nine Mystical Powers, and Law Heaven and Earth...The world became quiet again, and the red dragon rolled over and continued its nap.This is the story of a red dragon who, after years as an overworked employee, finds himself reincarnated in another world.Devoid of the intrinsic knowledge and natural abilities of dragons, it wields other formidable skills.

After breaking up with his girlfriend, he accidentally acquired a genius system and rose from there against the heavens, becoming invincible..

- Description from Novelupdates

This is a cliché story about two young people saving the world.

The male student, Fukai Nagamasa, ignores his studies for college entrance exams in favor of following the path to chuunibyou. As he fainted during night cramming session before the exams, he realized that he was transported to a parallel world as a feudal lord in the Sengoku Era. Not to mention that suddenly, he was marrying the sixth Demon King, Oda Nobunaga’s little sister, the one who was purported to be an unrivaled beauty?