How I Met Your Mother: 10 Shadiest Things Barney Has Ever Done

We have heard a few times throughout the series that Barney has used promises of marriage as a way to sleep with someone, but in the case of Abby, he had already slept with her. This time, the fake engagement was simply to make Ted, who had recently cut Barney out of his life, upset.

As you can imagine, this plan does not work out well for Barney, backfiring almost immediately due to Abby being a bit empty-headed. She calls her mother to tell her the good news, and starts to plan their magical wedding. Once Barney realizes that this isn't upsetting Ted however, he retracts his proposal very fast, and informs her that it was all a bit to get back at Ted.

He used a poor, albeit naive, girl to get back at someone that is supposed to be a friend of his. This is not something that you would do to anyone, let alone a friend. Proposal is nothing to joke around about with someone that cares for you, but as we can clearly see Barney has no conscience.