By The Grace Of The Gods (manga) 01

Slime's up for one recently deceased middle-aged businessman! Equipped with magic, young Ryoma undertakes a carefree existence in the forest, leisurely learning more about his new abilities and surroundings. And when he encounters slimes like those in video games from his former life, Ryoma uses his newfound magical powers to get creative with his research! Will the gods get more than they bargained for in Ryoma?!