Yes, right. Good thing Wei Ying has such a tiny waist, because he slips it on him quite nicely and then zips it up; the only thing that the dress can't quite handle is his broad chest. These darts were not made for Wei Ying.

The tulle underneath the dress give it a little bit of body, and turn Wei Ying into a veritable hourglass, though it's a tad bit short on him, stopping at his ankles. Lan Wangji takes off his own overcoat to drape it on Wei Ying, thus making him look like a princess with that dress cut so high, such a feminine silhouette.

From behind, he takes the other dress and places it over top of Wei Ying's hair, draping it over to appear as a veil, and slides his arms around Wei Ying's tiny waist, looking at the both of them in the mirror as they would see each other at the wedding.