Future Ted is telling his kids about how Robin went through the regular stages of figuring out when and how to say "I love you" in comparison to his "I love you" on his first date with Robin.
From Ted taking care of her when she was sick, killing spiders for her, or when he offered to take her sister to the empire state building. Instead of saying "I love you" she said "Falafal"
Robin and Lily are waiting at the airport for Katie, Robin's 17 year old sister, to arrive in New York. Meanwhile, Robin is telling Lily about the Falafal incident, and how she's never said "I love you" to anyone before. Katie walks into the terminal, and Robin gets excited, but then Katie starts making out with some guy, which freaks out Robin. They walk up to Robin and Lily and she introduces her boyfriend Kyle, who was also visiting family in New York. Katie tells Robin she'll be staying with him their first night, which Robin refuses. Katie tells her that its an important and special night for them.
Robin is downing a drink, and tells the gang that she cannot believe her little sister is planning on losing her virginity, and asks the gang to help her
Lobby of the Empire State Building
Robin finally got Katie to stay the night with her, and the group take her to see the Empire State Building. Robin and the group try to tell Katie that waiting is a good thing, and that she should wait for something special. Marshall and Lily saw how great it was to wait for eachother, and now they're engaged. Robin and Katie argue about it, and Katie walks away to smoke. Everyone then recounts their first time, and ages.
Barney's First Time
It's a scene straight out of "Dirty Dancing" from the clothes, the music and the hair. Barney and Baby are singing to each other on the floor of a dancing room.
The group cuts his story short because they know its directly from "Dirty Dancing."
Marshall and Lily's First Time
Marshall and Lily are in bed in Marshall's dorm room. They cannot wait to have sex, but Lily wants to make it special. They plan on getting a room new years eve, which, according to Marshall's expression, is too far away. But they agree to wait.
12 minutes later, they just had sex, and say oops, because they didn't wait. But it was great for the both of them.
Robin says that their story is adorable, but Ted says, tell them what happens next.
Back to Marshall and Lily's First Time
Lily asks if Marshall wants to do it agian, and we hear Ted say "Please don't" and see that he is sleeping on the top bunk of the bed in which Marshall and Lily just had sex.
Robin's First Time
Robin was 16 and it was with her boyfriend at the time, Brian. He gets in position, but then rolls off, and says "Yeah, I'm gay."
Robin says that even though they just barely had sex, it counts. She explains that he didn't dive right into the pool, but splashed around in the shallow end. Lily says that it doesn't count, but Robin and Marshall says it does. We find out that Marshall wasn't officially Lily's first, because her highschool boyfriend, Scooter, "splashed around in the shallow end." This upsets Marshall, and Lily tries to show that it doesn't count, only he counts. She compares it to being in the Empire State Building Lobby, even though they're in the lobby, they're not really at the Empire State Building yet. Marshall doesn't agree with the analogy, and says it still counts.
Katie thinks that Robin is being a hypocrite, because Robin has probably had sex with a bunch of guys. Robin defends herself saying she's had different levels of feeling for each guy. Katie counters, and asks Robin if she loves Ted.
Ted takes Robin aside, and tells her that its ok, she doesn't have to say it. He's fine with it, which makes Robin feel a lot better.
Robin talks with Katie, and tries one more time to talk Katie out of it, they end up not going up to the Empire State Building.
Future Ted tells his kids that Katie did do it, and got pregnant with quintuplets, lived in a trailer park and became an alcoholic and died. Which was a lie, he just tried to scare his kids.
Marshall and Ted's Apartment
Robin comes over to Ted's to tell him that Katie didn't sleep with Kyle. Apparently Katie asked to wait, and Kyle broke up with her. We find out that Ted spoke to Katie, and got through to her, by telling her his first time story.
Ted's First Time
Ted is making out with a girl named Molly and she tells him she loves him, and he says he loves her, too. (Ted voice over: "But, I didn't") They then proceed to have sex. 12 minutes later, Ted gets up and gets dressed to go light some fireworks with his cousin. Ted promises to call Molly (Ted voice over: "But, I didn't"), and gets ready to go, but then asks to borrow $20 which he'll pay back, (Ted voice over: "But, I didn't").
After telling this story, Ted shows Katie that 17 year old guys will do anything for sex, even the nice guys.
Robin says that Ted's story doesn't sound like something Ted would do, which is true.
Ted's REAL First Time
Ted is making out with a girl named Molly and he tells her he loves her, and she says she loves him, too. They then proceed to have sex. 12 minutes later, Molly gets up and gets dressed to go light some fireworks with his cousin. She promises to call Ted, and gets ready to go, but then asks to borrow $20 which she'll pay back.
Robin is touched by Ted's story, and hugs him, and tells him that she loves him.
Lobby of the Empire State Building
The group goes back to the Empire State Building, Barney asks why, because they were just there yesterday, and Marshall says it didn't really count. Lily hears this, and proves to Marshall that Scooter didn't really count. The gang then gets into the elevator, and goes up.
The gang realizes they never head Barney's real first time story. Barney tries to pull off some stories but they're really scenes from other movies like; "Fast Times at Ridgemont High", "Risky Business", and "War Games." It turns out that he was 23, and it was with his mom's 45 year old divorced friend, Rhonda. Barney is obviously distraught, so Marshall allows Barney to re-tell his "Dirty Dancing" story.