Basically ZEROSENSE is like a god who wants to make sense of fnafuck and it's many many flaws, due to the fact that fnafuck is basically what I consider to be "the joke fnafb", however him doing so will destroy said universe of fnafuck.

As for what the shit a remnant is, a remnant in this case is basically like a clone which is also a critique of the original version. So, with freddy fuckboy, his critique is that his series, or at least the main series, is dead; this is despite the complete collection, btw.

As for what OTHER remnants there are... yeahnonotgonnashowyouthatlol.