It looks like the youngest Jonas Brother, Nick, is the last brother off the market.  He is allegedly dating Ms. Universe 2013, Olivia Culpo.

Jonas and Culpo were first seen together when they co-hosted this year's Miss USA pageant, according to International Business Times.  And, last week the two were seen on a romantic date, according to E! Online.  

An eyewitness told E! that Jonas, 20, and Culpo, 21, were seen dining together at Ovest Pizzotecca in New York City.

"Nick was leaning in towards her across the table like she was saying something really important," the source said.

"They looked really happy when they walked together," the source said about the couple walking down the street hand-in-hand.  "Me and my friend both agreed they were, like, swinging their arms all happily."

Reps for both celebs couldn't be reached for comment, but the restaurant did confirm Jonas was there that night.

Before arriving at the restaurant, the two were seen leaving Jonas' apartment.

"They were holding hands and there were fans standing outside," the source told E!. "As soon as they saw the fans, they stopped holding hands." Then Culpo continued to walk up the street while Jonas stopped to talk to fans.

What do you think of the new couple? Let us know below.