JOVOESCREPTE

// ==UserScript==
// @name         e621 Pool Stuff
// @version      0.1
// @description  Shtuff
// @author       Chronos Ouroboros
// @match        https://e621.net/post/show/*
// @match        http://e621.net/post/show/*
// @grant        none
// ==/UserScript==

//176827
//Previous: <a href="/post/show/">&lt;&lt;</a>
//Next: <a href="/post/show/">&gt;&gt;</a>

var links = document.getElementsByTagName ("a");
var previousLink = "";
var nextLink = "";

for (var i = 0; i < links.length; i++) {
    if (links [i].innerHTML == "&lt;&lt;") {
        previousLink = links[i].href;
        break;
    }
}
for (var i = 0; i < links.length; i++) {
    if (links [i].innerHTML == "&gt;&gt;") {
        nextLink = links[i].href;
        break;
    }
}

document.onkeypress = function (e) {
    e = e || window.event;

    if (document.activeElement.tagName.toUpperCase() != "TEXTAREA" &&
        document.activeElement.tagName.toUpperCase() != "INPUT") {
        if ((e.keyCode == 101 || e.keyCode == 69) &&
            (nextLink != ""))
            document.location.href = nextLink;
        else if ((e.keyCode == 113 || e.keyCode == 81)
            && (previousLink != ""))
                document.location.href = previousLink;

        if (e.keyCode == 119 ||
            e.keyCode == 87)
            window.scrollBy(0, -40);
        else if (e.keyCode == 115 || e.keyCode == 83)
            window.scrollBy(0, 40);

        if (e.keyCode == 97 || e.keyCode == 65)
            window.scrollBy(-40, 0);
        else if (e.keyCode == 100 || e.keyCode == 68)
            window.scrollBy(40, 0);
    }
};