One Piece: The Strongest Swordsman - Chapter 89 - 88: Gecko Moria (2)

Payload specialist, Tang Yue, who is a mechanical and electrical engineer by training, is left stranded on Mars when he receives news from his AI robot assistant, Old Cat, that Earth has exploded. He believes himself to be the last human in the Universe.

I became the Heavenly Demon’s dog.

Xiao Ran transmigrated to a fantasy world. As a dungeon guard in the Celestial Dungeon, with a special floor called the Purgatory meant for powerful demons and martial arts experts, he faced a huge challenge from the start. The Eldest Princess acquired a forbidden martial arts technique and was banished to the Purgatory. However, no one was powerful enough to restrain her. All the dungeon guards were defeated. Xiao Ran stepped up and declared, “Your Highness, it’s better for you to behave yourself on my territory” and effortlessly subdued the Eldest Princess.

He progressed from imprisoning the Eldest Princess to delivering the Great Xia Kingdom from the evil clutches of various demons and evil martial arts experts.

…

Xiao Ran was the mastermind behind the scenes.