I've never seen this guy do genderswaps and it's tagged as yuri at pixiv. And even if this was genderswap or even futa, Meiling still has her trousers on so I don't really see this could work.
The front flap of Meiling's top is drooped over to the side and it's not uncommon for pants to have zippers, is it? Even if it's not a zipper just like an opening with a button, like guys' boxers.