gugudan SEMINA

gugudan SEMINA is one of those K-pop names that still pops up in fan group chats even years after the curtain came down. If you’re searching for gugudan SEMINA member profiles 2026, you’ve landed in the right spot. This guide walks you through everything — who’s in the band, what each idol brings to the table, and what these talented women are up to in 2026.

Let’s set the scene first. gugudan SEMINA (구구단 세미나) is a sub-unit, or subgroup, of the South Korean girl group Gugudan. It’s a trio made up of three members — Sejeong, Mina, and Nayoung — whose name is literally built from the first syllable of each of their names. Clever, right? The unit was formed by Jellyfish Entertainment and debuted in 2018 with a self-titled single album.

Here’s the thing fans need to know going into 2026: gugudan as a whole, and its sub-units including SEMINA, officially disbanded back in December 2020. But that doesn’t mean the story ends there. Two-thirds of this trio — Sejeong and Nayoung — are very much in the spotlight in 2026 thanks to a major I.O.I reunion, while Mina has carved out her own lane in acting. We’ll cover all of that below, so stick with us.

Throughout this article, you’ll see key terms bolded — things like member profiles, K-pop idol bios, girl group facts, and discography — because these are exactly the phrases people search for when they want to learn more about a K-pop subunit like this one. Let’s dive in.

Before we zoom in on each member, let’s cover the big picture. Think of this section as your cheat sheet — the kind of info you’d want at your fingertips before a trivia night with fellow fans.

gugudan SEMINA stands out in the K-pop world for a simple reason: it’s not a randomly assembled promotional unit. The three women involved had already shared a journey together long before SEMINA existed — they trained together, competed together on a reality show, and even debuted together in another group first. That shared history is what gives this trio its chemistry, and it’s part of why fans still talk about them years later.

So, what exactly made this group tick? Here’s a quick checklist covering the essentials.

• Group Name: gugudan SEMINA (구구단 세미나)
• Type: Sub-unit (subgroup) of the girl group Gugudan
• Number of Members: 3
• Members: Sejeong, Mina, Nayoung
• Agency: Jellyfish Entertainment
• Country of Origin: South Korea
• Debut Date: July 10, 2018
• Debut Release: Self-titled single album “SEMINA,” led by the title track “SeMiNa” (also written “샘이나”)
• Name Origin: Formed from the first syllable of each member’s name — Sejeong, Mina, Nayoung
• Genre: Pop, dance-pop
• Status (as of 2026): Disbanded (alongside parent group Gugudan, effective December 31, 2020)
• Notable Connection: All three members first appeared together on Mnet’s survival show Produce 101, which also led to them debuting in the project group I.O.I

The Band Member Profiles

Now for the part everyone’s really here for — the member profiles. Each of these three women had her own role, her own personality, and her own fanbase within the group. Let’s introduce them properly.

Quick-Look Member Table

A quick note for accuracy: you’ll sometimes see Nayoung’s role listed slightly differently across fan sites — some call her the lead dancer and visual, others emphasize her rap line. That’s totally normal in K-pop idol profiles, since roles can shift depending on the era or the comeback.

Sejeong — The Face of the Group

Sejeong, born Kim Se-jeong, is arguably the most recognizable name in this trio, and for good reason. She’s gone on to build one of the most well-rounded careers among her peers, balancing music with a thriving acting career.

Sejeong

Her personal motto is all about persistence — try one more time, even when it feels like the end.

She loves painting as a creative outlet outside of music.

Rewatching old movies is one of her favorite ways to unwind.

She placed second overall on Produce 101, which helped launch her into I.O.I.

She was the very first Gugudan member to debut as a soloist.

Her soundtrack work and acting roles have made her a familiar face well beyond music charts.

She’s collaborated with other idols on duet tracks, blending her vocal style with different genres.

Fans often praise her stage presence for feeling effortless, even during high-energy choreography.

In 2026, she’s part of a major I.O.I reunion project, marking a decade since the original group’s debut.

Her versatility — singing, dancing, and acting — makes her one of the most consistently working idols from her Produce 101 generation.

Nayoung — The Leader and Visual

Nayoung, born Kim Na-young, took on the leader role for SEMINA, bringing a steady presence to the group while also handling vocal and rap duties.

Nayoung

Her go-to motto centers on gratitude and giving her best effort in everything she does.

Fans gave her the affectionate nickname “Shining Nayoung.”

She enjoys winding down by watching videos and listening to music in her free time.

She trained at more than one academy before joining Jellyfish Entertainment.

She was officially confirmed as a Gugudan member in June 2016.

As SEMINA’s leader, she often took the lead in interviews and showcases.

Her dance line in the group’s title track stood out for its sharp, dynamic choreography.

She balanced leadership duties with softer vocal moments on B-side tracks like “Ruby Heart.”

After Gugudan’s run ended, she shifted her career path while staying connected to her Produce 101 roots.

In 2026, she’s reuniting with former groupmates as part of I.O.I’s 10th-anniversary comeback, proving her staying power in the industry.

Mina — The Main Rapper and Maknae

Mina, born Kang Mi-na, brought energy and charisma as the group’s main rapper and youngest member, or maknae.

Mina

Her personal motto jokingly puts food first — no matter the situation, eating comes first.

She has a special talent for falling asleep almost instantly, no matter where she is.

Watching plays and traveling solo are two of her favorite hobbies.

She’s a big fan of the Harry Potter series.

She appeared on a variety show centered around — fittingly — eating well.

Her acting credits include notable K-dramas, showing her range beyond music.

As maknae, she often brought playful energy to group dynamics and interviews.

She was part of multiple Gugudan sub-units, not just SEMINA, showing how often she was tapped for special projects.

In 2026, she’s stepped back from group reunions like I.O.I’s comeback to focus fully on her growing acting career.

Despite sitting out recent group activities, she’s remained a beloved figure among long-time fans who followed her since her Produce 101 days.

Achievements

When you look back at what this trio accomplished, it’s worth remembering the context: SEMINA was a short-lived sub-unit project, not a long-running act with years of award show wins. Still, the unit and its members built a solid legacy.

• The trio’s pre-existing fame from Produce 101 and I.O.I gave SEMINA instant visibility upon debut, which is rare for a sub-unit.
• Their debut single album charted on real-time music charts in South Korea during its release week in July 2018.
• The title track “SeMiNa” earned consistent rotation on Korean music programs like The Show, Music Core, M Countdown, Music Bank, and Inkigayo throughout their short promotional run.
• Individually, the members have gone on to far bigger achievements — Sejeong’s acting and solo music career, Nayoung’s continued presence in the industry, and Mina’s acting credits all reflect well on the group that first brought them together as a trio.
• Their biggest “achievement” in 2026 might be this: two of the three members reuniting publicly through I.O.I’s 10th-anniversary project, proving the bond from their trainee days never really faded.

Discography and the Music Video

SEMINA’s discography is compact, but it tells a clear story — a short, sweet promotional cycle built around one main release.

• Album: SEMINA (self-titled single album)
• Release Date: July 10, 2018
• Title Track: “SeMiNa” (also stylized “샘이나”)
• B-Side Track: “Ruby Heart”
• Concept: The music video leaned into a colorful, comic-book-inspired visual style, filmed partly in Bali, with a fun “funky diva” theme that highlighted the members’ friendship and playful chemistry on camera.

The music video for “SeMiNa” gave fans a chance to see a lighter, more carefree side of three idols who’d mostly been known for their work in bigger groups. Bright colors, summery outfits, and group choreography made the visuals just as memorable as the song itself.

Live Performances and World Tours

This is where it’s important to be upfront with you: SEMINA, as a specific three-member sub-unit, never went on a dedicated world tour. Their live activity was limited to Korean music program stages during their July–August 2018 promotional window, plus a few variety show appearances.

That said, if you’re tracking these members’ live performance history more broadly — especially heading into 2026 — there’s a lot more to talk about. Here’s a table that lays it all out.

Tours and Live Performances Table

A few important notes on that last row, since it’s the big 2026 update fans are searching for:

• Sejeong and Nayoung reunited with seven other original I.O.I members for a 10th-anniversary comeback, releasing the mini-album I.O.I: LOOP in May 2026.
• The accompanying 2026 I.O.I Concert Tour: LOOP kicked off with multiple nights in Seoul, followed by stops in Bangkok and Hong Kong.
• Mina did not join this reunion, choosing instead to focus on her acting career and other prior commitments — a reminder that even within a tight-knit trio, members can take very different paths.
• As of mid-2026, there’s no confirmed plan for SEMINA specifically to reunite or tour, though emotional moments shared by members during the I.O.I promotions have fans hopeful for more group activities down the line.

Wrapping It Up

So there you have it — a complete look at gugudan SEMINA’s member profiles in 2026. This little K-pop sub-unit may have had a short run, but its three members, Sejeong, Nayoung, and Mina, each carved out lasting careers that fans are still following closely today. Whether you’re here because you just discovered their 2018 music video or because you’re tracking the 2026 I.O.I reunion, we hope this guide gave you exactly what you were looking for.

Got a favorite member or a memory from their debut promotions? Let us know — fan stories like yours are what keep groups like this alive in our memories long after the official activities end.