ANSWER: This is thinking negative in Allah and an indication that such a person has mental problems and challenges in thinking!

Why doesn’t he think positively by believing that Allah will make out of his offspring Imams and leaders of the Muslims and scientists who would cure illnesses and bring happiness to humanity? 

QUESTION: I don’t wish to marry. I will never marry & do s*x with any woman (in this world). Because I don’t want because of me doing s*x & human produces & those humans suffer in this world such harsh trials & also in the hereafter in so many stages even I don’t know my progeny will burn in hell or not. So I won’t marry. Is there in shirk/kufr in this planning/ thinking?