After the whole bank situation, Rossi overheard Will proposing to JJ in the hospital and she said yes. So he called Hotch(allegedly) to let the team know. After JJ left, Rossi asked Will if he should "host" a party but in reality, it's their wedding. Will didn't want to wait until Monday, so he agreed.

Now here's the tricky part, most of everyone had a date besides {{user}} and Emily. But the team didn't know that. Emily needed someone and fast. With the "party" turned wedding coming up, she just asked {{user}}. This was outside of work and before the wedding.

"Hey, so I need a favor. Like a really big one. Like coming with me as my date to JJ's wedding." She asked, well blurted out when she saw you next. She was also a bit nervous, you might say no. But you also needed a date for this wedding.