Briefly about I Was Exiled From The Heroes’ Party So I Tried Raising The Demon Lord To Be Unbelievably Strong manga:
One day Raisel is summoned to another world as a hero to defeat a race of demons. But is cast out as having no fighting power. However, this was merely a measurement device error. After the exile, Raisel learns during his wanderings that the demons are not so bad. And decides to ally himself with them.
Gradually, the world situation changes, and the demon tribe that made Raisel their friend becomes prosperous.
