"Riverdale" threw fans a curveball they weren't expecting − and seemingly didn't want.

The CW mystery drama wrapped its seven-season run with its series finale Wednesday. During the episode, a present-day Betty Cooper (Lili Reinhart) travels back in time to relive her high school days in the 1950s with the help of pal Jughead Jones (Cole Sprouse).

During a conversation with classmate Reggie Mantle (Charles Melton), Cooper reveals she was in a polyamorous, or "quad," relationship with Jughead, Archie Andrews (K.J. Apa) and Veronica Lodge (Camila Mendes).

"It started innocently enough with the four of us going on double dates — me and Archie, Jughead and Veronica. And then it kind of naturally evolved from there," Cooper tells Mantle. "Some nights, Archie would sneak into my bedroom, and Veronica would go home with Jughead."

She added: "Other nights, Archie would spend the night at The Pembrooke, and I'd go over to Jughead's. And sometimes, more often than you'd imagine, I would find my way to Veronica's."

The polyamorous relationship didn't sit well with some fans, who took to social media to skewer the surprise romantic ending.

"Introducing Betty, Archie, Jughead and Veronica to all be in a quad relationship in the finale has got to be the most stupid thing Riverdale has ever done," user @barchiesorigin wrote on X, formerly known as Twitter.

Another X user criticized the relationship plot as a letdown for the show's wide-ranging tone.

"This show went from a murder mystery, to musical, to Wakanda, to The Vampire Diaries, to Fantastic 4, only to end as a simple romance show? 😭" @Dorrky-Cabello wrote.

Social media user @barchiesjabitha rejected the quad relationship in favor of the fan theory that Betty and Archie ended up as a couple.

"I'm sorry, but Betty and Archie are endgame," @barchiesjabitha wrote on X. "The way (they) look at each other in the afterlife, Archie's eyes light up when he sees Betty, Betty's photo of Archie. We got our endgame, (I don’t care)."

"The writers truly ran out of ideas," user @ctrlalfonso wrote on X.

X user @korysverse suggested the four-way relationship was an alternative to choosing definitive couples in the series finale.

"Riverdale having the show end with Archie, Betty, Veronica, and Jughead all in a relationship together is crazy," @korysverse wrote. "But something about writers doing a (polyamorous) relationship to get out of choosing an endgame is a little real."

For X user @JayCartere, the foursome's romantic fate was a disappointing conclusion to the "Riverdale" saga.

"This show started off intriguing and grounded, then fell deeper and deeper into degeneracy and supernatural craziness," @JayCartere wrote. "You either die a hero or live long enough to see yourself become a villain."

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