Sou Yurugi

A young pharmacologist and researcher in Japan died from overworking, and was reincarnated in a Medieval Parallel Europe. He was reincarnated as a 10-year-old apprentice to a famous Royal Court pharmacist, had attained an inhuman skills of ability to see through disease, material creation, and material destruction. In a society in which dubious medical practice are rampant, price gouging thru the monopoly of the pharmacist guild, and good medicine aren't available to the commoners. He was recognized by the Emperor at that time and opened a Pharmacy at the corner of the town. He will wipe out the fraud that has swept the world, and deliver to the commoners a truly effective medicine that was developed using present day pharmacology. Thus the boy pharmacist will cheat by using his previous knowledge to create innovative medicines while helping the people of the parallel world, a story about living his new life to the fullest this time.

After saving humanity from the despicable Demon King, Leo Demonhart does not earn a hero’s standing. Instead, he is regarded with suspicion and hostility by those he fought to protect. Treated as a pariah with nowhere else to turn, exiled Leo seeks a position in the army of his former nemesis! But the army is not what it once was before its defeat at Leo’s hands, so to maintain his new position, Leo must whip the forces back into fighting shape.