Many of Ted and Victoria's firsts (first kiss, first night together, first weekend together) all happen in the span of a weekend. After being asked by Marshall and Lily how many times they had sex over the course of the weekend, Ted reveals that they are waiting, as they do not want to rush into things too quickly. He then adds that it was mostly Victoria's idea, and the only reason he's going along with it is that he thinks Victoria might be the one. Ted begins to get anxious after a few weeks and can't stand it. However, Victoria decides to speed things up when she realizes that she will be out of town when their first month together ends. They go back to Ted's (supposedly) deserted apartment, and spend a lot of time just being together before they actually go to the bedroom to have sex together for the first time.
At the same time, Marshall and Lily are actually in the apartment. They had planned on going to a small bed and breakfast for their nine-year anniversary, but decided to bail on that plan and stay home and have a much more mellow anniversary. Ted and Victoria unexpectedly show up, trapping them in the bathroom. They first make fun of Ted and Victoria for being a mushy new couple, but Lily begins to wonder what happened to the romance in their relationship. She and Marshall try just staring into each other's eyes, but Lily ruins it when she asks about dry cleaning. They then try just holding hands, but Marshall ruins it by sneaking an arm around Lily and caressing her breast. As they begin to wonder if they're out of "firsts", Lily realizes that she has to pee. She hasn't peed in front of Marshall before, and always wanted to keep some of the secret protected, but eventually does pee in front of Marshall. Although not happy at first, she realizes that this was a first for her and Marshall, and then realizes that their relationship is not stale.
Robin is left out on her own, and after a friend hooks up with someone, she decides to become Barney's "bro" for his "bro-ings on around town" that night. Robin shows up in a suit, and Barney is impressed. After hanging out at the cigar bar, they go play laser tag. They go back to the bar, where Robin tries to hook Barney up with a woman and Barney tries to hook Robin up with a lesbian. They both return to Robin's apartment to play Battleship. Barney misinterprets their camaraderie for sexual chemistry, and takes his clothes off in a failed attempt to seduce Robin. After yelling at Barney, Robin admits that she has feelings for Ted, and Barney promises not to tell, on the condition that she not mention Barney's going "bare pickle" in front of her.