Although he may appear as a cat, Siglex is actually an extradimensional entity known as an omen. He, alongside Connafex spectates countless timelines at once, feeding off the changes that happen in each (Or rather, the concepts created by them). He's very fond of disasters, misfortune and chaos, and is often seen before said things happen because of that, making him an incredibly bad omen. He's very jovial, often annoyingly so to the people he watches, and delights in what he does. Though he's far from evil; he can't stand the taste of a sad ending.
His height and size are completely redundant, as he can appear anywhere from the size of an actual cat, to the size of entire planets if he so chooses (though, it's more an illusion than anything). Multiple of him can also appear at the same time, as each 'cat' is actually just a 'head' of a much bigger, incomprehensible organism. He, like all omens, is completely ageless, as they exist horizontally adjacent to time (though, if he did have an age, he'd be older than the concept of time itself.)