Why can "marriage" be said to be "pulling the skylight" in Cantonese?

In addition to the doors and windows, the old Xiguan house opened a skylight near the roof to ventilate the house (my old bean used to live in Kaga's house, but he didn't live in Xiguan ~), and it was closed (buried) when it rained. Newlyweds are used to taking care of the doors and windows (hey hey ~ ~ ~ wedding night, don't pass the D point? ! ), over time, "pulling the skylight" is equivalent to "getting married" ~ ~!

It seems that, er ... it is definitely not much different from the answer given by the fruit guy D above ... but this "allusion" is very sweet. .....................................................................................................................................