Look, it was a joke!
Zayn and Louis had to dress up as girls for a month and go to one of those Girl's Club meetings every Wednesday, without giving out the information that they were really guys.
It was a drunken decision, actually. A stupid game of 'Never Have I Ever' led to it. And now he was wearing a toilet paper stuffed bra.
Maybe he regrets it, but not all of it - it is how he met Ellie.
