Let's say that the skill was only known to the three fools and they somehow reported it to the king. Now, what do you think a king who'd execute an innocent person without a second thought would do? Kill the dude who can grant you pseudo immortality? Oh hell no! He'd sure as hell silence the...
So far pretty good.
P.S. Never summon a stereotypical SJW to your world, never. Ik that this hero ain't an SJW but he sure does act like one. (has meltdowns, thinks the dude's trying to build a harem, doesn't fully listen to what he says, etc.,)
P.P.S. The whole summoning thing lies in a grey...
These authors need to invest more brain cells for naming their manga. Look at this dude, he got employed in the friggin description! unemployed my ass.