LESTER: It's the weirdest thing. I feel like I've been in a coma for about twenty years, and I'm just now waking up.
Once Lester comes across Angela at his daughter's dance performance, all his emotions (well, lust primarily) get stirred up, and he remembers what it's like to feel passion again. He didn't realize how dead inside he'd been feeling until… he didn't feel that way.
ANGELA: It's okay. I'm used to guys drooling over me. It started when I was about twelve. I'd go out to dinner with my parents—every Thursday night, Red Lobster! Every guy there would stare at me when I walked in, and I knew what they were thinking. Just like I knew guys at school thought about me when they jerked off.
Here, Angela is reassuring Jane that she totally doesn't mind that Lester was perving on her at the basketball game. Angela's whole self-image seems to revolve around sex—or more specifically, who wants to have sex with her (and she also takes care to make others think she's promiscuous). We later learn it's all a front.
ANGELA: You were defending him! You love him! You want to have, like, ten thousand of his babies.
We don't know it quite yet, but Angela's not really as worldly and experienced as she likes to pretend—and it kind of shows here in her teasing. Sure, she's joking, but even the humor is kind of immature and reminds us that she's still a young girl, not the sexy vamp she's trying to be.
ANGELA: It's that psycho next door. Jane, what if he worships you? What if he's got, like, a shrine with pictures of you surrounded by dead people's heads and stuff?
Ricky immediately takes a shine to Jane and starts filming her. Naturally, since Ricky is a stranger, Jane finds that pretty creepy (and Angela too, obviously). When this conversation takes place, Ricky has just written Jane's name in fire outside the house. So, you can understand why people might think he's a little scary. Turns out, though, that he is genuinely interested in Jane, and the pair strikes up perhaps the only really functional relationship in the movie.
JANE: I'm serious, though. How could he not be damaging me? I need a father who's a role model, not some horny geek boy who's going to spray his shorts whenever I bring a girlfriend home from school.
Unfortunately, Lester's new lease on life comes with a lot of embarrassment and mortification for Jane, since he's perving on her closest friend in a completely unsubtle and inappropriate way. As Jane alludes to here, Lester's reawakening—however awesome it is for him—just looks like immaturity to everyone around him.
FRANK: What did he make you do?
Frank says this to Ricky after he sees Ricky and Lester doing a drug deal and (mistakenly) thinks they're engaged in oral sex. He is not happy.
LESTER: Whoa, whoa, whoa. I'm sorry. You got the wrong idea.
After Ricky and Frank fight about what Frank thinks he's seen, Frank heads over to confront Lester. Well, we think he's there to confront him, but it turns out that he's there to pursue some sexytimes with Lester—he's been hiding some seriously secret same-sex leanings. Unfortunately for Frank, Lester is not gay, so he has to gently brush Frank off here.
ANGELA: I still want to do it. I just thought I should tell you, in case you wondered why I wasn't… better.
Late in the movie, Lester and Angela end up in a situation where they could actually get frisky, and Angela admits to him that she's actually a virgin. In that moment, he suddenly realizes that the Angela of his fantasies is totally fictional, and the girl in front of him is really a child. So, having had that epiphany, he stops their little moment in its tracks.
ANGELA: She's… she's really happy. She thinks she's in love.
Just a few seconds before his death, Lester is thrilled to hear from Angela that not only is his daughter happy, but she's also in love. Angela finds that whole idea ridiculous, but Lester doesn't—and that news gives him a nice, peaceful moment before Frank sneaks up behind him with a gun.