[Loki hears the question, loud and clear as if Billy spoke it out loud. It's the question he is always asked. The question he can't answer, for a multitude of reasons.

He sighs.]

Destruction for its own sake is pointless. [Though he could envision a future in which he became so bored that he'd still find nihilism better than gibbering madness.] As is cruelty.

[Another sigh. He traces a finger around the top of his tea cup.]

But sometimes things we think are terrible must happen, in the service of preventing something even worse from coming to pass.