Fans Tear Up Over I.O.I’s 10th Anniversary Stage

I.O.I’s 10th anniversary project is ending on a deeply emotional note, and fans have one more reason to tune in. The project group will appear on KBS 2TV’s music talk show The Seasons: Sung Si-kyung’s Eardrum Boyfriend for what Korean reports describe as the final broadcast of its anniversary activities.

The June 5 episode brings together four very different acts: actor-singer Cho Jung-seok, I.O.I, ballad group 2AM, and rookie crew CORTIS. That mix matters because the lineup stretches across several eras of Korean pop culture, from 2010s survival-show nostalgia to veteran vocal stages and new-generation performance energy.

For I.O.I fans, the emotional center is clear. The members are expected to revisit video letters they recorded 10 years ago, then leave new messages for their future selves. Korean coverage says the moment brought the members to tears, turning a promotional appearance into a kind of time capsule for a group that has always carried a special place in K-pop history.

I.O.I Brings the Anniversary Full Circle

I.O.I was formed through the first season of Produce 101, the survival program that helped define a new era of audience-driven idol projects. The group’s original run was short, but its impact lasted far beyond its official disbandment. Many fans still see I.O.I as the blueprint for later project groups and as a rare case where a temporary lineup built a lasting emotional bond.

That is why this 10th anniversary project has been watched so closely. Earlier this year, the group opened official channels for the anniversary campaign, giving fans a formal place to follow reunion content. English-language K-pop coverage also framed the move as a major signal that I.O.I’s anniversary would be treated as more than a simple throwback.

The upcoming appearance on The Seasons now gives the project a broadcast finale. Korean reports say the members return with a more mature image, while still carrying the playfulness that longtime fans remember. One reported talking point is the group’s humorous “no overly sultry behavior” rule during preparation, a phrase that hints at how carefully the members balanced nostalgia with their adult selves.

The video-letter segment is the most meaningful detail. Ten years ago, I.O.I left messages for the members they would become. Seeing those messages again on a late-night music stage gives the reunion a clear emotional structure: the past speaks to the present, and the present answers back.

Cho Jung-seok Turns a Love Song Into a Live Moment

Cho Jung-seok adds another kind of story to the episode. Best known internationally as an actor from projects such as Hospital Playlist, he has also built a second public identity as a singer. On this episode, he appears as a second-year vocalist and joins host Sung Si-kyung for the duet corner “Two People.”

His biggest highlight is the first live performance of his recent single, whose Korean title translates roughly as “After I Met You, Everything in an Ordinary World Became Good.” Reports say Cho connected the title to his wife, singer Gummy, explaining that meeting her made him feel that way. It is a simple detail, but it gives the stage a personal frame that casual viewers can understand quickly.

Cho is also expected to sing one of Gummy’s songs and show a surprise dance cover inspired by BTS’s Jungkook. That combination turns his segment into more than a standard actor appearance. It presents him as a performer who is willing to move between romantic ballad, personal storytelling, and playful pop performance without treating any of it as a gimmick.

For viewers who followed his earlier music-show appearances, the stage also continues a longer arc. Cho has spoken before about Gummy’s advice and support as he stepped more publicly into music. This episode turns that background into a fresh live moment, with Sung Si-kyung serving as both duet partner and interviewer.

2AM Reopens the Memory Box

2AM’s appearance leans into a different kind of nostalgia. The vocal group is expected to revisit hit songs associated with some of the most familiar ballad and variety moments of the late 2000s and early 2010s. Jo Kwon brings back the comic energy that made his “Kkap Kwon” persona famous, while also singing “We Fell in Love,” his duet with Gain.

Lim Seul-ong is set to perform “Nagging,” the duet linked to IU, and Lee Chang-min reportedly takes on parts originally associated with both Gain and IU. That setup gives the segment a built-in sense of humor. It also reminds viewers how often 2AM moved between serious vocals and variety-show looseness during its peak years.

Jinwoon adds another bridge between music and screen. Korean reports note that he recently drew attention through the hit film The Man Who Lives with the King, and he is expected to share a light behind-the-scenes story about facial-hair makeup making him hard to recognize. Like Cho Jung-seok’s segment, it shows how Korean entertainment often blends acting, music, and talk-show personality into one broadcast.

CORTIS Gives the Episode Its New-Generation Charge

CORTIS rounds out the lineup with a sharply different energy. Korean coverage describes the group as bringing a raw, free-spirited stage, with an average age of 19.2. That number becomes part of the episode’s comedy when Sung Si-kyung reacts to the generation gap and asks the members whether they even know him.

The group is also expected to discuss the “Young Creator Crew” nickname and the “Young C-C” meme that has recently followed them online. For younger viewers, that gives the episode a current social-media hook. For older viewers, it creates an easy contrast with I.O.I and 2AM, whose segments are built around memory and return.

One reported exchange between member Sunghyun and Sung Si-kyung centers on the difficulty of studying foreign languages. It is a small detail, but it helps soften the gap between senior host and rookie performers. Instead of presenting youth only as noise and speed, the show appears to give CORTIS room to talk about growth and pressure.

Why This Episode Stands Out

Music talk shows often rely on star booking, but this episode has a clearer theme than a normal variety lineup. Every guest represents a different relationship with time. I.O.I is looking back across 10 years. 2AM is reopening songs tied to a specific generation of Korean pop fans. Cho Jung-seok is using music to mark a personal chapter. CORTIS is introducing a younger audience to its present-tense identity.

That structure is why the episode has more value than a simple broadcast notice. It shows how Korean entertainment keeps recycling memory into new stages, not only through reunion concerts but through talk shows where artists can explain what those songs and images now mean to them.

Fan comments collected in Korean coverage point in the same direction. Viewers expressed anticipation for I.O.I’s full-group stage, Cho Jung-seok’s first live performance of the new song, 2AM’s familiar hits, and CORTIS’s appearance alongside senior acts. The excitement is spread across generations, which is exactly what the episode’s lineup seems designed to create.

The Seasons: Sung Si-kyung’s Eardrum Boyfriend airs June 5 at 11:10 p.m. KST on KBS 2TV. For I.O.I fans, it may feel like the closing page of a long-awaited anniversary chapter. For everyone else, it is a compact snapshot of how Korean music television turns memory, romance, humor, and new talent into one stage.