You might wonder where Marshall and Lily are, and if you are Saget!Ted's kids you will be told creepy stories about your aunt and uncle wanting to make a baby. They have the candles and the music to set the mood (soft sounds) and the music for actual baby-making time (banjo music). Lily's readying it all at home and Marshall's getting ready to leave work.
Back at the dibs battle, Barney tells Ted that if he ignores the dibs, Barney will give a speech at his wedding to this girl in which he outs Ted as a dibs ignorer. This leads to a fantasy sequence in which the bride slaps Ted for humiliating her with his implied dibs, apologizes to Barney for not knowing and they decide to do it right there, at her and Ted's reception. Ted tells Barney to have at it, since the hottie has her shields up anyway, reading a book. Barney's like, "At a bar! The book might as well be called, Are You There, Barney? It's me, Horny." He says "shields up" actually looks like... oh, let's just have Robin walk in looking haggard. And so she does. And because her messy hair, dirty and baggy clothes, and makeup to make her look sick aren't enough, she's also carrying bags of junk food. Just so we know she's really in a bad place, hurting from the breakup with Don, that guy we never cared about because the show didn't want us to.
Flash to a few months earlier, just post-breakup. Ted tells Robin he's there for her, and she tells him that when she tries to have sex with him, he has to try to say no. He's all, I'll do more than try; our friendship is too important. She rants about how awesome she is and how he won't be able to resist. Then he walks in two weeks later, and she's gross and shoving food in her face when she tells him she's ready to have sex now. Back in the present, Ted finds a week-old Cheeto in Robin's hair, which she calls dibs on and then eats. Barney tells her she's exquisite, which he means sarcastically, but which I actually believe to be true more here than almost any other time. Because she's just reveling in this. Anyway, Ted asks her if the girl at the bar has her shields up. Robin says she is; she's here on a date and is reading while she waits to impress the guy she's meeting. Robin bites into a burger and gives Barney a "de-rection."