The second lead syndrome is a term most commonly used to describe K-dramas when fans root for the second lead or begin to fall for them.
The female lead usually ends up with the male lead in Korean dramas, but just because it's scripted and written that way doesn't mean viewers don't deviate from the male lead to root for those in the background.
Especially when the second leads are equally charming, endearing, and attractive. Here are some Korean dramas that will give you major second-lead syndrome:
1. While You Were Sleeping

While the second lead in Korean dramas can have a tough exterior in some cases, Han Woo Tak is an exception. Woo Tak is a gentle, caring, and soft friend to Nam Hong Joo and Jung Jae-Chan.
While he's always in the background, it's difficult to ignore his longing moments with Hong Joo and the fact that his phone background is a silhouette of the two together.
While You Were Sleeping is a legal drama/fantasy film about three young adults who have developed the ability to see the future through their dreams: field reporter Nam Hong-Joo, rookie prosecutor Jung Jae-chan, and police officer Han Woo-Tak.
2. Reply 1988

Kim Jung Hwan of the hit series Reply 1988, arguably one of the most beloved second male leads of all time, will undoubtedly make this list.
He's always had a crush on his childhood friend Sung Deok Su, but he's never told her about it.
And when he realises Choi Taek feels the same way about her, he takes a step back for the two of them. Respectful and selfless, it's no surprise he won viewers' hearts.
3. 18 Again

Ye Ji Hoon, a pitcher in 18 Again, is one of Korea's biggest baseball stars. He falls in love with Kim Ha Neul after she interviews him.
A popular trope in which every girl wants him but he only has eyes for one, their relationship is a fairytale romance that unravels as his feelings for Da Jung remain strong.
4. True Beauty

True Beauty's Han Seo Joon is caught in a love triangle with stars Lim Joo-Kyeong and Lee Su-Ho, based on the popular webtoon.
Hwang In Yeop has completely impressed viewers with his accurate portrayal of Han Seo-Jun, as many fans have noted. As we learn more about his family and how protective he is of Joo-Kyeong, it's difficult not to root for him.
Especially in his hidden moments of pain and in the finale, when we see how affected he is by Joo-Kyeong. True Beauty gave fans major Second Lead Syndrome and seeing Han Seo-Joon not get the girl was heartbreaking.
5. My Roommate Is A Gumiho

The series, based on a webtoon, follows Shin Woo Yeo, a 999-year-old nine-tailed fox determined to become human, and Lee Dam, a university student majoring in history.
When we first meet Gye Sun Woo, Lee Dam's popular senior in college, he appears to be the stereotypical arrogant character.
He bets on Lee Dam's affection and appears to be drawn to her difficult demeanour. However, as the show progresses, we see actual character development and how he continues to pursue her. It's difficult not to root for him, even though we know it's not going to happen.
6. Start-Up

With a cast that included Bae Suzy and Nam Joo-Hyuk, it was inevitable that Kim Seon-Ho would catch the attention of viewers.
His character, Han Ji Pyeong, is the stereotypical male lead with a tough exterior, which makes it all the more heartbreaking when we see glimpses of his tender moments throughout the show.
From bonding with Dal-Mi’s grandmother to help her to keep the secret of Nam Do San’s true identity. Set in South Korea's fictional Silicon Valley called Sandbox, Start-Up tells the story of people in the world of startup companies.
From bonding with Dal-Mi's grandmother to assisting her in keeping Nam Do San's true identity hidden. Set in South Korea's fictional Silicon Valley, Sandbox, Start-Up tells the story of people working in startup companies.
7. Crash Landing On You

Yoon Se-Ri is the heiress of a South Korean conglomerate. An accident caused by strong winds forces Yoon Se-Ri to make an emergency landing in North Korea one day while paragliding. She meets Ri Jeong-Hyeok, a North Korean army officer, there. He tries to protect and conceal her.
Ri Jeong-Hyeok soon falls in love with Yoon Se-Ri. Kim Jung Hyun's portrayal of Seung-Joon was one of the most wholesome character development moments in K-dramas history.
While his story ended in the most heartbreaking way possible, he did it in the same manner as the other scenes. And the famous passport scene will never leave us.
8. Love In The Moonlight

Crown Prince Lee Yeong's transformation from a boy to a revered monarch, as well as his unlikely relationship with eunuch Hong Ra-on, is the subject of the series. It's difficult to compete with Prince Yeong's charms, but Yoon Sung was a convincing case for second lead syndrome in this period drama.
Although it was obvious who Hong Ra On would end up with from the start, it still tugs at your heart to see Yoon Sung continue to love her - even from afar.
Without giving anything away, the ending is the salt in the wounds that really makes you feel for him.
7. Extraordinary You

The series follows Eun Dan-oh, a high school student at a prestigious academy. Bae Kyung is arrogant, rude, and cruel to Eun Dan Oh, so we have no reason to like him.
At least, that's what we believe. There's more to this show than meets the eye, and once we see his character development, it's difficult not to sympathise and root for him.
It's obvious that Dan Oh and Haru will end up together, but that doesn't take away the weight of second lead syndrome.
8. Cheese In The Trap

The drama centres on the lives and relationships of a group of university students, particularly the difficult relationship between Hong Seol, a hardworking scholarship student, and Yoo Jung, a deceptive senior.
Jung is wealthy and well-known, and he is the heir to the Taerang Group. Although he appears to be kind to everyone around him, he is quite manipulative, with a penchant for annihilating those who irritate him, often through the use of others.
Although she is unsure of his character, they begin an awkward relationship that is complicated by the distance between them as well as the fallout from his various schemes.
The arrival of Baek In-ho and his sister In-ha Jung's childhood friends who have since feuded complicates matters even further.
It's one of the few shows where many fans disliked the male lead from the start, and the fact that the male lead is portrayed as a sociopath doesn't help matters. Baek In Ho, a tough rebel who plays the piano, is easy to root for with his earnest character and the genuine moments he shares with Hong-Seol.
9. The Heirs

The show follows a group of wealthy, privileged high school students as they prepare to inherit their families' business empires, overcoming obstacles and growing along the way.
While Kim Woo Bin's Choi Young Do is definitely introduced to us as the antagonist, his redemption arc does grow over the course of the show, and it had many viewers rooting for him over the ever-charming Lee Min Ho.

10. Boys Over Flowers

The show is about a working-class girl who becomes entangled in the lives of a group of wealthy high school boys. Lee Min-role ho's as F4 leader was diametrically opposed to his role in Mackerel Run, which earned him international acclaim.
As the female lead begins a love/hate relationship with Gu Jun Pyo, most fans enjoy Yoon Ji-Hoon's role as the second lead. He is sweet, caring, consistent, and protective, and he is there for her in her darkest hours.
11. Nevertheless

"Nevertheless" is a drama that tells the story of Yu NaBi, an art student who does not believe in love but falls for the flirtatious nature of Park Jae-Eon.
Many fans were disappointed that he did not marry Yu NaBi. Fans were thrilled to see Han SoHee and Song Kang on screen together, but Park Jae-Eon was not the best guy for Yu NaBi to date. To put it mildly, their relationship was perplexing.
And it makes sense; how could anyone resist our "Potato boy"?
If you're someone who always falls for the second lead, these dramas are for you.

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