It's pretty clear that, as the primary antagonist, John will be around until the end when he is (presumably) defeated. Honestly, as weird and ugly as he is, I find his scenes (less so in this update, but in general) do a lot to keep the tension ramped up and the dread high. I'm not generally a fan of his sort of content in other games, but in this one, I've enjoyed the glimpses of him running around wrecking random women (and Silvia) as both a twisted mirror and a potential endpoint of the MC's behavior.