Steinhardt's Guide to the Eldritch Hunt

From the introduction:

Easily distinguished by their eyes—brightly coloured irises that swirl like galaxies in a jet-black sclera—demidritch occupy a precarious precipice in the minds of Luyharnians, equal parts revered and abhorred. Born of a union between humanoids and eldritch beings, demidritch are often referred to as ‘half-angels’, a misnomer arising from Luyharnians’ mistaken belief that these creatures are descended from celestials. Stories abound of radiant silhouettes—eldritch creatures wreathed in powerful illusions—appearing unto pregnant Luyharnians and blessing their progeny with otherworldly powers.