Sage Monarch - Chapter 70: The Power of Twenty Megamammoths

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?

In order to live he must get close to girls, what kind of rule is this? Tang Zheng possess the Nine Yang Saint Body, a rare body constitution that is hard to come across within a millennium, yet he must absorb pure Yin energy to stay alive. In order to live, he will fight! Absolute campus belles, goddess teachers, charming housewives, haughty lolis… all kinds of woman walk into his life causing him to be surrounded by beauties!

- Description from Novelupdates

One day, I woke up only find out that I’d become a Demon Lord, an individual responsible for protecting a dungeon. The world I’d been spirited away to was one filled with violence. Gigantic monsters wandered through it and competed with each other each and every day for the right to survive. I had no choice but to strengthen my dungeon’s defenses in hopes of living another day—or at least that was what I’d thought. For some odd reason, I instead ended up spending my days in relaxation and bliss.

The story is centred around a cute android who initially had a happy life with her master who dearly loved her. But she was then struck by a series of misfortunes and ended up in a robot-equivalent of concentration camp. Through experiencing and witnessing the sufferings towards herself as well as the people/robots around her, she eventually gained a better appreciation of life.