1. Izzie and Alex (Grey's Anatomy)

Despite Alex's attempt to spite Izzie by posting her old advertisements, she decided to befriend him anyway until he broke down his outer exterior. It took a few seasons (and kisses) before their relationship turned into the comforting one it became, but it was clear to the audience how much the two cared about each other.

2. Lady Mary and Matthew (Downton Abbey)

Lady Mary is originally very hostile towards Matthew simply because he is not upper class like her and he is usurping her inheritance. The two take a while to develop a proper friendship, but Lady Mary's opinion of him changes after he rescues her younger sister, and she comes to regret her former opinion of him.

3. Bonnie and Enzo (The Vampire Diaries)

These two had a rocky start when their first meeting consisted of Enzo threatening Bonnie's current boyfriend, Jeremy, with death, but over time, their need to work together resulted in their later romantic relationship.

4. Damon and Elena (The Vampire Diaries)

As Damon had first intended to seek revenge on his younger brother, who Elena had fallen for, she did not speak highly of him. But her ability to see through him while remaining unafraid allowed her to see that there was a spark of redemption within him and they developed a tentative friendship that later blossomed into an all-consuming love for each other.

5. Logan and Veronica (Veronica Mars)

Logan and Veronica start off as enemies at the beginning of the series due to their history with each other, but as many fans recognize, their romantic relationship is one that creeps up on you, and the series has developed a following that demands closure even after the sudden cancellation of the series.

6. Haley and Nathan (One Tree Hill)

While this one applies more to the first season, Haley does start tutoring Nathan so that he will stop tormenting her friend, and this evolves into a steady relationship that many fans consider to be the core couple of the show.

7. Cheryl and Toni (Riverdale)

If there's a solid reason to keep up with "Riverdale," these two are it. Cheryl's initial hatred of anything having to do with the Southside strikes up a dislike for Toni who is a proud member of the local gang, but Toni's continued persistence in discovering who Cheryl is beneath the facade she puts on causes Cheryl to open up, and more of Cheryl's character is revealed as she makes herself vulnerable in front of Toni, portraying one of the healthier versions of this trope.

8. Brandon and Rowan (T@gged)

A recent favorite of mine, Brandon falls in with the crowd that labels Rowan as an outsider, and he initially does little to deter his friends' insults towards her. But when they are forced to work together on a school project, Rowan admits that Brandon is not a bad guy even though he acts like one. Their development throughout the second season is one of my absolute favorites as they are vulnerable with each other in a way that allows for personal and relationship growth, and Rowan never excuses Brandon's actions, indicating that they are aware of the other's mistakes while allowing them to learn.

9. Bellamy and Clarke (The 100)

I was a little iffy about adding this to the list as they are not—and have not ever been—together, but their development remains astounding all the same. Bellamy regards Clarke as one of the privileged prisoners, writing her off as a "princess," but when circumstances force them both to take on leadership roles, their relationship becomes more amicable, and at their current point, the two are very important to each other. I have hope in their romantic development, but regardless, their bond has shown how nuanced human relationships are.