If I die, it'll be on your conscience.

如果我死了，那将是你的良心。

If something is " on your conscience, " it's bothering you.

如果某件事是“在你的良心上”，它就会困扰你。

You don't want this young man's blood on your conscience.

你不想让这个年轻人的血沾染你的良心。