Porky is such a fantastic villain. You're left so completely, utterly torn on whether he really is a complete monster, or perhaps even slightly sympathetic. I still can't decide, myself.
What I find most disturbing about him is how he so clearly idolizes Ness, even declaring his actions in MOTHER3 to be in his name. But to be more specific, he idolizes a very twisted illustration of Ness that only ever existed in his mind, born out of a fearful worldview exacerbated by loneliness.
He doesn't talk about it all that much in your time with him in MOTHER3's final hours, but what's mentioned, what's seen - the Friend's yo-yo... it hits hard.
And his fate - his fate... hmm... It's clear he sees it in the moment as the ultimate victory - forever insulated from anyone that wouldn't like him, the world he's deathly afraid of. But - would being isolated forever - even when the sun burns out, as noted by Itoi - serve as a fate worse than death, or perhaps - he's too far-gone to care? Has he gotten his just desserts? Is this what he wanted, truly? There's no answers to any of that. You can only wonder.
One can only ponder, if Ness had, in another time and space, stumbled upon the capsule and saw such a sickly shell of his neighbor poking his tongue out from the capsule's window, unknowing of what he had done in the Nowhere Islands, how he became what he did. There is a piece of fanart depicting this and it is absolutely gut-wrenching.