Dud was working adult, with dual thought capability and the author is still making him dense as a rock!
By his own admission, he was so busy he never had a girlfriend. All the money he made from his work went towards rent. He most likely never had a female childhood friend or had any girl show interest in him, as he had no money to spend. Also, he is not overly handsome, he is rather average in looks.
What normal reincarnated guy would think 3 top-tier beauties with large oppai would be interested in him sexually in 1 to 4 weeks?
Plus women are skilled liars, no normal person reincarnated or not would detect their true feelings unless they had a mind-reading skill or had a relationship meter showing who likes, loves, is indifferent, hates, or despises him.