This is based on opinion. Please don't list it on a work's trope example list.
Tear Jerker / The Girl Next Door
When Matthew and Danielle share their first kiss. Matthew just takes charge and kisses Danielle and everything slows downs and they got lost in the moment.
After Matthew takes Danielle to the cheap motel.
Danielle: Isn't that what you want? To fuck a porn star in a cheap motel room? So this is what you really think of me.
Matthew: Why didn't you just tell me?
Danielle: Because I didn't want to! Because I loved the way you looked at me.
When Matthew tells Danielle she is all he cares about.
Matthew: The only thing I care about is you. You know? All I want is for us to go back to normal again.
When Matthew tells Danielle she is the best thing that has ever happened to him.
Matthew: You're the best thing that ever happened to me, okay?
When Matthew gives a crumpled paper to Danielle and says to her "I just want you to know that I know who you really are, and you're better than this." Danielle then uncrumples the paper and it is the drawing she made of the girl with lipstick at the table with Matthew that she gave him.
When Matthew asks Danielle to the Prom.
Matthew: Will you go to prom with me? ....What?
Danielle: I would love to.
When Matthew gives his Moral Fiber speech with Danielle looking on.
Matthew: Moral fiber. So, what is moral fiber? It's funny, I used to think it was always telling the truth, doing good deeds, basically [mumbling] being a fucking boy scout. But lately I've been seeing it differently. Now I think moral fiber's about finding that one thing you really care about. That one special thing that means more to you than anything else in the world. And when you find her, you fight for her. You risk it all, you put her in front of everything, your future, your life, all of it. And maybe the stuff you do to help her isn't so clean. You know what? It doesn't matter. Because in your heart you know, that the juice is worth the squeeze. That's what moral fiber's all about.
When Danielle thanks Matthew for taking her to the prom.
Danielle: Thank you.
Matthew: For what?
Danielle: I never went to prom.
When Matthew and Danielle have sex for the first time. In the Directors Commentary the director Luke Greenfield describes it as follows "This scene. My first love scene i have ever shot. Was a scene of loss of innocence. Matthew's losing his virginity and Danielle's making love for the very first time."
Luke Greenfield: This scene. My first love scene i have ever shot. Was a scene of loss of innocence. Matthew's losing his virginity and Danielle's making love for the very first time.
When Matthew sent Kelly a box of cigars. The note on the box.
Matthew: "The Juice Was Worth The Squeeze"
Matthew's last line of the film
Matthew: [narrating] And of course, I'll never forget the girl next door. As for me, I'm just goin' with it.