When she pulls back from the kiss, her arms naturally retreat to her sides, and Beca Mitchell notices exactly 2 things. Which is rather weird because she's in the middle of a huge auditorium place thingy and she's just been crowned (ok, along with the Bellas, but she's the one with the pitch pipe and Oh God this a cappella thing is getting to her much more than it should. She'll vehemently deny being this attached to something so nerdy when she's made it in the music industry as a DJ, obviously) as the National champs of Collegiate a cappella. People are clapping and cheering and she's pretty sure somewhere on the stage, Aubrey is yelling at her because the Bellas have a tradition to uphold, one that does NOT include her running up the audience to kiss the head treblemaker. But whatever, she's a badass like that. Besides, Aubrey IS leaving next year and Beca DID lead them to their first victory in EVER (but who's counting) so she's entitled to some slack.
The first thing she notices is Jesse's goofy little grin and dazed expression on his face, like he's just won the happy-ending lottery. Jesse, who has a borderline obsession with movies and soundtracks and scores. Jesse, who at first she thought was a bit of a weirdo (because seriously, to this day she still thinks he might have been stalking her at the beginning of the year) then turned out to be a decent guy. Jesse, who got her to actually watch "The Breakfast Club" and for that, she'll be forever thankful (as will the Bellas, she's sure). Jesse, the guy with the juice pouches and Rocky. Jesse, who is fun and kind and everything a girl would want in a boyfriend. But for everything that Jesse is, he most certainly is not, and Beca's absolutely, positively certain of this, her prince charming. Her knight in shining armor. He's not THE ONE. Nope, she thinks as her line of vision drifts elsewhere, he's definitely NOT. So when he leans back in for another kiss, Beca can't stop him fast enough, and she honest to God does not mean to be rude when she bursts out laughing. Because it took a girl less than a week to see her naked and him a whole school year to kiss her.
Yep, he's definitely gonna have to wait until hell freezes over for a second kiss.
(Later, when all was said and done and Jesse's found himself a girl who absolutely adores all his quirks and loves his huge movie collection, they'll look back and genuinely laugh at that moment. Sure he was the a cappella boy and she was the a cappella girl and they didn't end up having aca-children, but they did become something likes best friends and that's as good an ending as any.)
The second thing Beca notices happens to be on that stage right here, right now. It's weird how even though there's Aubrey and Stacie and Fat Amy (Fat Patricia?) and the rest of the girls whom she's gotten so unexpectedly close to, her eyes rest on one single person. She has literally been in front of Beca ALL ALONG (because the girl is tall and it's hard not to notice her presence every time she enters the room. Beca always chalked it up to her overly bubbly personality and tendency to invade her personally space) and she almost can't believe how she could've overlooked the ginger with the overflowing enthusiasm. The girl who just barges into peoples' (or perhaps, ok fine, she hopes, just hers) showers and practically force them into doing a spontaneous duet with her. In the middle of the night, Beca might add. It's all so crystal clear to her now, like one of those cheesy epiphany montages they do in Hollywood rom-coms, where the heroine would realize too late that she had loved her best friend from the very beginning, except this is real life, and there's nothing and nobody stopping her. Because Chloe is right there. She's right there and she's actually not going anywhere. Chloe is going to be staying at Barden to get a graduate degree and Beca's staying to lead the Bellas to their second consecutive ICCA's victory (ugh, what have they done to her).
What happens next is a blur, as they say. A blur of red hair, warm, soft lips and catcalls (from Fat Amy or Cynthia Rose or Stacie, she doesn't know. Strangely, she finds herself not caring). A blur of "I told you so" and "You bitches all over me 50." (After, Fat Amy will deny any and all allegations of her having a bet on how long it would take for them to get together).
They say that if you want a happy ending, it all depends on where you end the story. Beca thinks it's not when. It's who you end the story with that matters. And for a while, she thought Jesse might have been her happy ending (not like that, perverts). He was always the most obvious choice, from the very beginning with their little "meet cute" her first time on campus. But when Chloe leans in again and it feels like all the breath's been sucked out of her lungs and there are fluttering feelings in her stomach, Beca's brain just shuts down and she stops thinking altogether.