MTL - Marvel: Trading From the Ninja World - Chapter 2 Trading System

Reborn into a failing noble family, Liu Xingchang awakens in a weakened teenage body, surrounded by humiliation and betrayal. Once the revered Sword God of the Northern Polar Heaven Domain, he now faces ridicule from his former lover, Yu Qiuer, who has abandoned him for a rival, and scorn from the very man daring to tread on his legacy.Though his power has diminished to a mere third-grade cultivation, Liu’s indomitable spirit drives him to reclaim his path to supremacy. When he fatally strikes his foe amidst the disbelieving crowd, even the noble Princess Qingyuan is drawn to this fallen “”coward’s”” defiant strength.Can Liu Xingchang resurrect his family’s honor, ascend to the Divine Realm, and turn the tables on those who scorned him?

However, he did not know that he was not raising just a harmless pet, but a biological weapon secretly made by the government… a real monster.

As a former librarian, Rand felt that he had been living an ordinary life, the one that he had reclaimed unconsciously every single day.

Recently, he has been a little upset because the pet fish he accidently brought home to raised seems to have undergo some strange changes

Well, it turned into a merman.

- Description from Novelupdates

The cold star reflects the halberd, the moon shines on the bow, and the dragon bird and the snow are startled at night.

Outside of Qianshan, Banzhi’s fame is in the hometown of Yinhua Huoshu.

“I, Rong Taotao, will one day be the master of those nine stars.”

That year, a young man with a small schoolbag, a natural scroll on his head, and a Fang Tianhua halberd said this on the rooftop.

…

Easy and funny, welcome to the pit.

The work “Nine Stars Poisonous Milk” has been completed in 4 million words, and you are welcome to read it.

- Description from novelbuddy

A novel revolving around being transported to another world with an op system. The mc spends his day chasing skirts and doing missions to level up. A standard journey to the top with lots of girls from various animes and games with a twist of that gaming feel (hunting mobs, doing missions).