とは何ぞやと考えた結果、「服に染み付いたの汗の臭い」という結論に達しました。
虫の死骸の匂いとか夕立前の空気の匂いとか、もうちょっと風流なものは無かったんでしょうか。無念でなりません。
せめておんｎ・・まあともかく無念でならんわけですよ。

I thought about what the heck that might be, and I reached the conclusion that it's "the stink of sweat soaked deep into clothing". Maybe it's something a bit more tasteful, like the smell of dead insects, or of the air just before an evening shower. Well, I don't regret it. At least it could've been a woman's—...well, anyway, it's not like I regret it.