Yoon Se-ri in Crash Landing on You or Scarlett in Search:WWW for choice. The outfits don't look too flashy even when they're wearing really bright colours and I love the way they accessorised with gorgeous shoes or statement jewellery.

Actually both Son Ye-jin and Lee Da-hee in general have great styling. Loved Da-hee's look as Kang Sa-ra in The Beauty Inside too.

I have a couple who come to mind

For the women:
-Seo Yea-ji in IOTNBO has to be the first for me.
-Kim Min-Jung in The Devil Judge
-Son Ye-Jin and Seo Ji-hye in CLOY
-IU in Hotel Del Luna

For the men:
-Song Joong-Ki in Vincenzo.
-Lee Jong-Suk in RIABB
-Gong Yoo in Goblin
-Lee Min-Ho in TKEM

I actually wrote a theme of the month post like this a few years ago! For me, the main one would be Park Shin-hye in Heartstrings. Her summery uni-student wardrobe was iconic. She was the one who awakened me to my love of little t-shirts tucked into full-length skirts. It's all I wear now.
But also:
-Hong Seol's yellow jumper in Cheese in the Trap
-Song Ji-won's long pineapple cardigan in Age of Youth 2

I will steal Bae Doona’s wardrobe in Stranger S1. They. Are. So. Cool.

Seo Yea-ji in "It's Ok to Not be Ok." Such gorgeous, distinctive clothes that not only looked stunning on her, but also represented the character's emotional contradictions. A perfect wardrobe for a fairy tale goth princess with impulse control issues.

Aesthetically, I also loved PMY's pencil skirt/silk blouse outfits in "What's Wrong with Secretary Kim," and in terms of being perfect for the character, Kim Hye-soo's track suits and gaudy jewelry in "Hyena."

For men, SJK's perfectly tailored suits in "Vincenzo" gave him the gravitas he needed to pull off that character.

Honorable Mention: Kim Woo Bim's teeshirts in Our Blues because they perfectly accent his very admirable biceps :)

For the women
- IU in Hotel Del Luna
- Kim Seo-young in Mine
- Yoon Soo-hee's Kim Hwa-Goon in Ruler : Owner of the mask.
- Chu Ja-hyun in My Unfamiliar Family

For the men

- Lee Gyu-han in She Would Never Know
- Gramps in Business Proposal
- Kim Jae-wook in Temperature of Love.

Run On's Oh mijoo and Dan Ah's outfits I liked.

While I'm a fan of PMY's pencil skirts in Secretary Kim & her lady-boss pant-suits from Her Private life...... they feel a little one-note to me.

However, ever since I saw Kurumi Mashiba in Kikazaru Koi Ni wa Riyuu ga Atte I've been wanting to raid her entire wardrobe. Including her lounge-wear! T_T The Tasaki accessories, color-blocking and her shoes really brought together every single silhouette she ever wore :D I believe there's even an instagram fan-page documenting every little detail of all her outfits, and the best part is, it isn't even un-achievable! ^^

Ps. Special shout-out to Seo-Dan's over-coats from CLOY that were particularly enviable & lust-worthy! For men, i would say a healthy mix of Huaze Lei and Xi Men's wardrobe from Meteor Garden 2018! ^^

Seo Yul , no competition.

Min Jae's suits in "Dali and the CP". He's suits were as bright and unique as his personality. I love them.
Sae Bom's comfortable clothes in "Happiness". Her clothes describe her personality well. And I think she's the first FL I've seen wearing that kind of clothes for the whole drama LOL. SB is iconic.
Bong Hwan-ah's hanboks in "Mr Queen". They were just too pretty.
Woo In looking badass in "Doberman" when she wears the pink wig, sunglasses and leather jacket.
Jang Na Ra in "Sell Your Haunted House". She looked great, like a badass. It fits her personality very well.

Everyone in "Tomorrow" when they wear the black suits. PS. I can't get over the bling bling boots HS was wearing like two weeks ago.

I thought Vincenzo's collection of suits were absolutely stunning. All the Business Proposal clothes for the guys and the girls were beautiful. Hari's clothes for the first Blind Date were perfect. Yoon Seri in Crash Landing was always beautifully dressed, and the same applies for any drama where Son Ye-Jin appears. See Ye Ji in Its OK Not to be OK looked amazing throughout, and I do hope we will see her back soon.

I have a bit of a weird fascination with all KDrama high school uniforms - they are so different to the versions with which I am familiar, and often feel quite high maintenance! But, common to global teens, there is the need to customise... To that end, I loved Moon Ji-woong in 2521 - his great reveal under his uniform of the t-shirt which had been worn by the criminal - and the reaction it drew - was glorious, and was perfect for pointing us to the way he would thrive as an adult. Loved it!

Agree with all the comments praising Lee Dahee in Search:www, Seo Yejin in It's ok to not be ok, Kim Min Joon in Devil Judge and in Mr Sunshine. In a less sophisticated style, I also loved Nana's looks in Into the Ring and Kim Hye Soo's tracksuits in Hyena. They all looked stunning and I had a huge crush on every one of them while watching these dramas. As for male actors, Song Joonki in Vincenzo and Park Sunghoon in Psychopath Diary both look like a million dollars.
I'm still watching A Business Proposal, and the four main characters all have great styling, specially Kim Se Jeon while disguised - she really threads the line without coming off as tacky

1. Dali from Dali and Gamjatang
2. PM Ku(?) in The King: Eternal Monarch

Gimme all their wardrobes and I’ll be a very happy clam.

I would not steal this wardrobe because it only works if you are an ancient monkey god - but Lee Seung Gi’s wardrobe as Son O Gong in Hwayugi was iconic. So many excellent coats!

Women: Seo Ye Ji, IOTNBO
Shin Min Ah, Hometown Cha Cha Cha

Men: Lee Min Ho, The King: Eternal Monarch
Jang Hyuk, Money Flower

Sageuk edition: Hang Jin Yi, My Country

Since I embrace the minimalist life style, the glomorous wardrobe from the iconic female leads (IU in Hotela De Laluna, Sohn Ye-jin in CLOY, Seo Yea-ji in IOTNBO) I don't want to steal. But I really want to have Jung Ryeo-won's office wardrobe in Diary of Prosecutor. The style is just this unisex, tends to be tomboyish, comfortable and practical. She never used high heels and that drama, just that darn stylist flat shoes. I want them too

Okay well first, we have to get the iconic looks that have shaped/are my brand out of the way:

The Pink Sunglasses Club, but mostly their founder, Ah Si's Hot Pink Sunglasses in Meteor Garden 2018. (MG18 also had good coat porn, and the iconic Pineapple Hair :P)

Everything Seo Ye Ji wore in It's Okay to Be Not Okay, but specifically the Jester Skull Umbrella- I still want it. Really badly. I just don't have $800 to drop on an umbrella right now.

The Purple Suit Club- Lookout, Vincenzo, and because they still technically count, Monthly Magazine House and now just recently, Crazy Love.
(There's also the Purple Suit/Hanbok Club: Sageuk Edition but the only one I feel like listing right now is Bead Boy's.)

- The Umbrella Sword in 9Tails, just for like, having an umbrella that turns into a sword, but it would be nice if one day it were the real deal... :P

I have a LOT of opinions about costume design, as like an actual narrative tool, but for now I'll just list other stand out favourites that don't fit the above category, that I can remember right now:

- Ji A/ Jang Nara in Sell Your Haunted House
- The Coat Porn in Hwayugi (The Monkey King, my love, unfortunately I'm still salty they toned this way down in the second half for no reason, like excuse me, bring back the obnoxious and the drama, please)
- The Hanboks in Moonlight Drawn By Clouds, are still some of my favourite Hanboks ever. Especially Park Bo Gum's. A lot of sageuks have really beautiful hanbok and traditional clothing that are worth mentioning, but these always stand out to me and I'll forever be obsessed with them.
- Dali and Gamjatang, for me, mainly at the beginning, as I found it dropped off in signature flair in the latter half, but it still deserves a mention.
- Hwang Jung Eum's modernised hanboks in Mystic Pop Up Bar , especially the lipstick print one.
- The Secret Lyfe of My Secretary, for the contrast between Gal Hee and Fake Veronica, real Veronica's looks, especially her earring game, the suits, and for the show not only having a thematic purpose for Gal Hee's design, but keeping said design to the very end, and not makeover-ing it out.
- I know Byung Hee was more iconic for a lot of people, but I've always really loved the design for specifically Ji Hyuk/ Sung Joon in Shut Up: Flower Boy Band, which was just complimented by how he played him.
- Vincenzo in general

Random pieces I still remember for some reason:
- Key in Lookout
- the orange hoodie in Extracurricular
- the fact that the characters in Rookie Cops were colour coded? but like the show didn't really do anything interesting with that and sucked otherwise so
- the fluffy lime green angora type sweater that showed up in at least three dramas...
- can I saw LSH's styling in Scholar Who Walks in the Night even though I haven't seen it? hahaha
- Ki Seon...

For women it would be very hard to top Kim Nam-joo's wardrobe in MISTY, IU's wardrobe in HOTEL DEL LUNA or, for absolutely fitting into the drama's location, Park Min-young's wardrobe in I'LL COME TO YOU WHEN THE WEATHER IS NICE even though I will concede that her over-all wardrobe was perfectly stylish (and professional) in SECRETARY KIM.

For men- I do not think that it is possible to top Vincenzo's suits (and shoes) in VINCENZO not just because they were so sharp but because they so perfectly fit his character as a formerly high ranking mafioso From Italy. There is no way his character would ever wear anything else. Those suits did not just fit the man- they fit the part.

I have disliked more wardrobes than what I have liked. I did not like secretary Kim it was a bit too much “I am your secretary I am your sexy subordinate with no rights of my own” vibes. Similar to what one would expect women in mad men to wear in the 1960s. Soo Yeji wardrobe was again something I did not like since that would only suit someone very tall and very thin (which she is) so non replicable. My favourite wardrobe is Victoria song from find yourself. I loved a blue outfit she wore, so much so that I looked for a similar coloured outfit (I never do this). I also liked the outfits in Shen Rouxin wore in Rational Life. She was an older lady but her clothes looked comfortable and stylish and colourful. I also loved the outfits that Jennifer Anniston wore for her Raplh Lauren job. They are timeless, comfortable (diverse since people who are plumper will also look good in them), and very classy.

Oh part two I guess slash me adding stuff whenever I think of them~

A Business ProposalI actually really liked Ha Ri's outfits when pretending to be Geum Hi, the checks, the patterns, the gloves etc, and I also liked the little details in her Team Manager's fits, especially the bold glasses and shoes. :P

I can't believe I scrolled to the end and no one mentioned Jun Jihyun aka Cheong Songyi from My Love From Another Star! She is the OG kdrama fashionista.

Otherwise, agree with the two ladies of CLOY and Seo Yeji in IONTBO.