In this case, from the images I googled and some KSP intuition - this plane has low wings, but the engines are directed only a tiny bit above the center of mass.
So pitch down would be a healthy amount (having none or pitch up makes some situations awkward), while low wings improve stability on turns at the cost of overall stability.
And in this manga - only the very last image looks 100% uncontrollable. Engines are angled just comically high up. If you try to compensate for it by angling control surfaces - you are giving up how much more you can pitch up, making the whole thing aerodynamically inefficient and unstable, while also complicating controls, because the angle to compensate would depend on the speed.