Boysmell primarily stems from bacterial breakdown of compounds in apocrine sweat, resulting in malodorous fatty acids, thiols, and steroids, with the specific mix of bacterial enzymes and individual genetics influencing the final scent. Key odoriferous components include branched unsaturated fatty acids like (E)-3-methyl-2-hexenoic acid, sulfanylalkanols such as 3-methyl-3-sulfanylhexan-1-ol, and steroids like androstenone and androstenol, a result of testosterone and bacterial action.