[flashback to Ted talking to Katie at the Empire State Building:]
Ted: Well, I don't know what your sister's freaking out about, either. I was your age my first time.
Katie: Oh, really?
Ted: Yeah, yeah. It was, uh, it was with this girl, Molly.
[flashback to Ted on his bed with Molly:]
Molly: I love you, Ted.
Ted: Oh, I love you, too, Molly.
[five minutes later:]
Ted: [v.o.] But I didn't.
Molly: That was amazing.
Ted: Look, I got to go.
Molly: Where are you going?
Ted: My cousin got some firecrackers from Mexico. We're going out to the woods to light 'em, it's gonna be awesome.
Molly: Well, will you call me?
Ted: Yeah. Yeah, I'll totally call you.
Ted: [v.o.] But I didn't.
Ted: Molly?
Molly: Yeah?
Ted: Can I borrow 20 bucks? I'll totally pay you back.
Ted: [v.o.] But I didn't.
[back to the Empire State Building:]
Ted: And I never saw her again. I told her I loved her, but... I just wanted to have sex. I-I would've said anything to make that happen, and that's exactly what I did. Look, I'm not telling you what to do. I'm just telling you what all 17-year-old boys are like. Even the nice ones.