Baka to Test to Shoukanjuu‎ - Volume 9, The Fourth Question

In this world, there is the beautiful mutual and telepathy love.

A supreme expert in the Immortal World had died, and a strand of his soul returned to its original body on Earth. Tang Xiu discovered with amazement that ten thousand years passed in the Immortal World, yet only a single year passed on Earth.

Ruthlessly betrayed by his lover and trusted friends, Tang Xiu found that his soul went back to his previous body on Earth, and, despite he spent 10,000 years in the Immortal World, just a year has passed on Earth and many things have changed. Having an unsurpassed knowledge, Tang Xiu will protect his loved ones and go back to the Immortal World to take his revenge.

- Description from Novelupdates

This novel is also known as From The Start, I Traded A Galactic Warship

After getting a trading platform three thousand years later, everything in the world has become an antique, worth a thousand gold.

But it was also learned that three years later, aliens invaded, human beings fell, and the dark starry era began.

In this era of unprecedented change in tens of thousands of years.

Shen Shi decided.

First trade a space battleship, and then talk about it.

then–

Battleships come to the world from outer space! Global shock! Starry Sky Era, open in advance!

- Description from novelbuddy

This book narrates the joyful cultivation tale of an ordinary commonplace university student and a cute and coquettish little fox.