Buffy and Spike had a famously tumultuous relationship over the six seasons they appeared on Buffy The Vampire Slayer together, with many fans becoming divided between Team Spike and Team Angel, it was the Team Edward or Team Jacob equivalent of the late '90s and early 2000s.
Despite how rocky their relationship was, and the fact that Spike is a vampire, the very creature that Buffy sets out to slay, fans of the Buffyverse still root for them to stay together and fight demon-related danger in Sunnydale.
Their Intense Chemistry
Even as enemies, there was an intense connection between Buffy and Spike. Angel was Buffy's original love interest and teen Buffy was absolutely infatuated with him despite his brooding nature and how problematic he was for liking her as a teen when he was hundreds of years old.
Spike and Angel also had a bit of a history, and Spike's entrance into Sunnydale caused immense strife in Buffy's life. However, Spike's chemistry with the Slayer did not go unnoticed as @Amphora23 points out. Many fans felt that Sarah Michelle Gellar and James Marsters' on-screen chemistry was apparent and abundant from the start, making Angel and Spike the superior couple.
The Ultimate Enemies-To-Lovers
Famously, Buffy and Spike have an incredibly tumultuous relationship throughout the show. As you would expect, Buffy and Spike were natural enemies when Spike first appeared in season 2, but by the end of the show, they were inseparable.
Being a vampire didn't stop Spike from pursuing Buffy, even going as far as to obtain a soul just to be a better man for her. His dedication is clear, and as @ellieross_ highlights, they practically invented the enemies-to-lovers trope and become one of the most powerful TV couples of the '90s.
They Were An Instant Fan Favorite
The show's original plan for Spike was quite different from what actually happened in the show. Twitter user @filmforvictoria comments on the fact that Spike's character was only intended for season 2, but James Marsters' on-screen chemistry with Sarah Michelle Gellar was so great that he was brought back as a main character in season 4.
Spike quickly became a fan favorite as a love interest for Buffy. After all, he was edgy and polar opposite to Angel. However, he was arguably just as problematic as he betrayed Buffy at times, not least by assaulting her and sleeping with Anya.
Spike Is The Ultimate Bad Boy Turned Good
Even though he was soulless, Spike still showed redeemable qualities. Spike was devoted to Buffy, and despite his vampirism, he opened up to those around her in an effort to be more involved in her life. He did all of this without having a soul, developing an especially close relationship with Buffy's younger sister Dawn.
Spike treated Dawn as an adult and actually telling her she was the key in human form, when so many tried to hide this from her, @aspic_tarantula points out that this makes him more redeemable than Angel, as he didn't make this much effort with Buffy when he actually had a soul.
Beautiful Love Story
Whilst they had their ups and downs, Buffy and Spike consistently came through for one another. As @presidentabby explains, Buffy and Spike's relationship develops in different ways throughout the show.
There are many complexities within their relationship that don't develop until the last season, Spike highlights to the Scoobies how lost they would be without Buffy's guidance, causing them all to feel guilty and for Buffy to be reinstated in her leadership role. This alone shows how much he cares for her wellbeing.
Spike's Redemption Arc
Much of Spike's character development focused on his redemption arc. So many characters in Buffy the Vampire Slayer made poor moral decisions as @slayerxvampire observes, yet they are not treated with the same hate that Spike is often given for actions that are within his biological nature.
Spike was originally painted as a villain, whereas Willow was painted as a good character from the beginning of the show. Eventually, Willow goes rogue after Tara's death and while Spike makes similar mistakes out of anger, the two characters are treated completely differently by many fans.
Buffy/Angel/Spike Is A Classic Love Triangle
As @FranklinLynam points out, the love triangle between Angel, Buffy and Spike really was a unique one. They were two vampires competing for the affection of the woman that was born to slay them.
Buffy clearly internally struggled with this situation, as shown when she kisses Angel whilst being with Spike and telling Spike she loves him before he sacrifices himself. As Angel was her first love she found it hard to resist him, even with Spike's presence as her primary love interest.
Spike Was The Better Man For Buffy
Spike's love for Buffy was pure and overpowering, proven by the fact he loved her even when he didn't have a soul, going to great lengths just to get one for her. @hellohenriques highlights that all along Spike has been the better man not just for Buffy, but in general.
Buffy's hesitance towards accepting Spike's affections only makes their relationship dynamic even more interesting to watch. And it's even more bittersweet as they come to accept their feelings for each other more in the final season as viewers don't get to see them as a couple for much longer.
Their Relationship Still Sparks Discussion
The relationship between Buffy and Spike often sparks controversy. As Twitter user @_ogbertthenerd asks what fellow fans opinions are on Buffy's relationship with Spike - proving that the couple can still spark discussion nearly 20 years after the show ended.
Their relationship isn't just controversial because one party is a vampire and the other human. In addition to this, Spike did some questionable things to Buffy, and Buffy often pushed Spike to his limits as seen in "Once More With Feeling" where Spike begs her to let him rest in peace despite her needing his help.
Just A Regular Vampire
For all his faults, Spike was just doing what he was programmed to do. As a vampire, Spike evidently had a thirst for blood, but as @angelscorneryt points out, he didn't kill any of Buffy's family members.
In fact, Spike was cordial to Joyce and had a close relationship with Dawn in the last seasons of the show. Additionally, Buffy does not kill Spike despite the fact she is trained to kill vampires, proving that their love really overcame all.
Source:gamerant.com