For the past four years, the hit NBC series This Is Us has introduced viewers to the lives of the expanded Pearson clan, covering generation after generation of dynamic, flawed, human characters. Whether focusing on parents Jack and Rebecca, or children Randall, Kevin, and Kate, the series knows how to discuss difficult human emotions in ways that resonate.

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The series has also maintained a real commitment to depicting romances in all their many forms. For better or worse, there have been many, many couples in the series so far. But some of them are definitely much better than than the others - and some of them absolutely make no sense at all.

Perfect Together: Carol and Abe

Carol and Abe Clark in This Is Us

Sometimes, all it takes is a single episode to show a lifetime of a relationship, and just how perfect two people are together. It took until the series' third season for viewers to get an inside look at the backstory of Beth Pearson's character - a backstory that included the loving relationship between her parents, Carol and Abe Clark.

A perfectly balanced relationship, Carol was just as firm and no nonsense as Abe was soft and loving. The few scenes they shared together, prior to Abe's loss, revealed a couple who had been together for a very long time, and loved each other no matter what. We just wish we'd gotten to see more of them.

Make No Sense: Cassidy and Ryan

Cassidy and Ryan Sharp talking in This Is Us

In its perhaps overly ambitious fourth season, This Is Us introduced more new characters at once than ever before. A character unfortunately included in that crop is the wholly unsympathetic Cassidy Sharp, a former soldier struggling with PTSD who returns home to her husband, Ryan, and her young son, Matty.

The show never once shows a moment between the couple of Ryan and Cassidy that should make us root for these two, before suddenly Cassidy is lashing out and hitting their son. Subsequent scenes of Cassidy longing for a reunion with her husband therefore ring entirely hollow.

Perfect Together: Kevin and Sophie

Kevin and Sophie having drinks on This Is Us

It's rare that a first crush and a first love will go on to become something much more than that. But in the world of This Is Us, it's been clear from the very beginning that no girl has been right for Kevin Pearson in the way that his first love, Sophie, was.

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Originally just his twin Kate's best friend, Sophie soon became Kevin's world, and the two of them soon fell hard and fast for one another. They married soon after graduating high school, and though it didn't work out, they just kept finding their way back to each other years later. Hopefully, they still will.

Make No Sense: Kevin and Olivia

Kevin and Olivia mid rehearsal on stage in This Is Us

Sometimes, it's believable that opposites attract. Some of the best relationships in television history have come as a result of characters who have nothing in common, and who initially can't stand each other, falling in love. But the utterly forgettable and uncomfortable relationship between Kevin and his costar Olivia was definitely not one of those.

Olivia never fit the world of This Is Us overall. Mean-spirited and highly judgmental, she was a bad fit for Kevin from the moment she was introduced on screen. Thankfully, their brief relationship truly was a brief one.

Perfect Together: Jack and Lucy

Jack and Lucy Damon in This Is Us

One of the things that makes This Is Us a truly unique television experience is the show's insistence upon being a truly multi-generational story. The show has traveled through many different time periods, across many different generations. But one of the best love stories the series has offered so far has only been glimpsed in the far off future.

The romance between the adult Jack Damon, now a successful musician, and his one true love Lucy, a former waitress, absolutely won viewers over, and it was clear that Jack was the same little baby they'd been watching all along in the present timeline.

Make No Sense: Kevin and Zoe

Sometimes, it feels like a series just puts two characters together purely because they can. That's even more true when they pair together a character with another main character's relative, just for the added drama of it all. In the case of This Is Us, this was exactly what happened when the series introduced Beth's cousin, Zoe, and immediately made her a love interest for Kevin.

Though these two had a nice storyline together in their travels to Vietnam, but beyond that, it was clear that this was a relationship that was never built to last - something that became incredibly clear when they discussed their differing views for their future.

Perfect Together: Jack and Rebecca

From the very beginning of the series, there has been a standard against which all romantic relationships have been measured: that standard, of course, is the practically fairy tale level romance between Jack and Rebecca Pearson.

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Over the course of the series, it's become clear that these two have had their ups and downs, including an unconventional first meeting, Jack's struggles with PTSD and alcoholism, and Rebecca's resentments over putting her career on hold. But through it all, their love won out over everything.

Make No Sense: Miguel and Rebecca

You could easily make the case that the relationship that eventually forms between Miguel and Rebecca makes sense, given the fact that they've bonded over shared trauma with the loss of Jack. But in the big picture, nothing about this relationship makes sense or feels right for the show.

In any of their scenes, whether in the immediate aftermath of Jack's death or the future where they're elderly and married, Miguel and Rebecca feel more like friends than a couple. The romantic chemistry has just never been there.

Perfect Together: Randall and Beth

Beth looking lovingly at Randall

Jack and Rebecca might be the gold standard that so many people measure their relationship against, but the truest depiction of love and partnership and what it means to be a married couple comes in the form of the relationship between Randall and Beth Pearson.

From day one, they have been undoubtedly loyal to one another. They've supported each other in their lowest moments, and helped one another to achieve their dreams, no matter how lofty. As the show itself states, life's always better with a little bit of R&B in it.

Make No Sense: Kevin and Cassidy

Cassidy Sharp and Kevin Pearson in This Is Us

Kevin Pearson is a character with a whole lot of problems. Selfish, arrogant, and struggling with various forms of addiction for the past few years, Kevin is prone to self destruct and not exactly act in his best interest more often than not. When his Alcoholics Anonymous support group recommends that all AA attendees not get into a relationship within the first year, what does he do?

Kevin not only gets in a relationship, but does so with a fellow addict and group member, the volatile, cold, toxic character that is Cassidy Sharp. These two have been bad news from day one, and the total lack of chemistry between Justin Hartley and Jennifer Morrison certainly doesn't help.

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