Okaaayyyy?
So he can't Murder.
I can see how a Japanese person would consider taking the rules in their own hands to kill a person who is tied up... would be murder.
I actually agree; under those circumstances, it is a moral stance that I completely share.
Now, I think the murder is justified... but it is absolutely "Murder."
Now, he escapes, pulls out a dagger, and is making a threat... and I'd call that fair game; Not Murder.
...
But that may not be Takumi-san's take on it, and the Restriction is coded from his instinctive belief to the core of his being, so... no problem.
.... no hay problemas....
... machts nicht, even....
.......
..... why did he say he can't "Kill?"
It seems an important question, since "Murder" only exists as an idea; it is the opposite of "Justifiable Killing."
Most laws are about describing the circumstances under which killing is not allowed in your local democratic society, and all the killings that don't meet those criteria are allowed; the ones that do meet that criteria are "Murder."
Basically, "Murder" is literally (not figuratively) the unjustified killing of a human being.
That's the word's meaning.
So... he can't actually commit murder?
That's awesome!
I'd be constantly concerned about that in an actual Isekai! Like with bandits and shit? Cos killing people really sucks, and if you can avoid it at all? That wouldn't be a check on your power, so much as a guide-rail you could lean on.
....
Besides, not like you can't "accidentally" start a (un)fair fight if some motherfucker honestly and desperately need killin....