Kimmel then asked the Colombian-born actress, "Are you careful about dating guys that are too handsome?"
Vergara replied, "At that point, yes, because I had just broken up with my ex [Nick Loeb]. I didn't want to go into a relationship with somebody that...I thought he was going to be too much work, because girls were throwing themselves at him. I'm like, 'Ay! No! Please, I want somebody normal.'"
Asked if she had actually witnessed women hitting on her hubby-to-be, Vergara said, "I've seen it. Girls don't care."
She added, "I mean, have you seen him? I mean, I understand. I don't judge them."
Meanwhile, men still hit on Vergara too, just not in front of Manganiello.
The stars began dating last July and were engaged by Christmas.
Figuring out who to invite to the wedding hasn't been easy, Vergara told Kimmel. The couple is trying to keep the list of invites to 400.
"We said, 'Two hundred for you, two hundred for me,' but my 200 is like family, so I couldn't invite many of my friends," the 43-year-old actress said. "The truth is that he gave me some of his, because I was in trouble. There were people from work that I needed to bring."