<p>I bought DS 3 pairs of slim straights from AE size 32"waist 36"inseam. All are baggy in waist. I don’t think it is possible to buy 31" waist with36" length unless custom tailored. DS needs to gain 10 pounds. He is taking a weight training class next semester. Just needs to eat lots of protein and some healthy fats while lifting to bulk up a bit.</p>