Sixteenth Basket of Mantaos

Imagine being forced to live, after death, as incorporeal bodies trapped in a vast space of nothingness for thousands of years, with nothing to do but exchanging past memories with other cohabitants (read: weirdos).  Everybody wanted out, but there was no way to leave the Void... 
Until one day, a young man was finally summoned, as a powerful but reluctant mentor, by a bubbly and motivated but completely naive young girl. Baiyi, finally out of the Void, was the only one who could save all of the other 32 souls from their prison and his summoner might just be The Key to their freedom.
However, Baiyi had to use the techniques and abilities the other souls had taught him throughout the years, and together with his own extensive knowledge of anime and game tropes from his shady and dangerous past as an otaku, to face the biggest challenge of them all: training the clumsy young girl he was forced to partner up with… into a competent sorcerer!

EndlessFantasy Translation 

Why Did You Summon Me？

The moment the Voidwalkers focused their attention on the task at hand, they easily reminded everyone that a group of professionals could very well perform miracles. In just three days, the strategy to save Noirciel had been revised, optimized, and finalized. The Alchemist Walker had completed the first part of the plan, using materials taken from Baiyi's collection.

The first component was a pale-blue cuboidal crystal named "Mindstone". It sounded like something a big purple guy would put into a metallic gauntlet, but this Mindstone was only a vessel to store a soul.

In this universe, the soul contained the mind, while the mind controlled one's power and sustained the soul. With this in mind, the Voidwalkers quickly realized that one of Noirciel's problems was the fragility of her host's body. It was impossible for such a body to store her angel spirit or Divine Energy. The body could not even preserve all of Noirciel's personality.

This One's Not Afraid To Die