JxJ becomes the latest Seventeen sub-unit
Jeonghan and Joshua have made their sub-unit debut as JxJ with the title track 12 o'clock, adding a third pairing to Seventeen's run of unit releases. The Bias List's review, published on 19 October 2026, places JxJ alongside DxS, the duo of DK and Seungkwan, and V8, formed by Vernon and The8.
That context matters because the review frames this as a sub-unit year for Seventeen rather than a full-group comeback cycle. According to the review, the group has been unable to make a full comeback while members serve their mandatory military enlistment. JxJ therefore arrives less as a side project than as part of a practical release strategy: keep the Seventeen name active while the full line-up is unavailable.
The review's immediate interest is not the strategy itself but the sound JxJ have chosen. Where the previous units are described as occupying very specific styles, JxJ are presented as more of a grab bag. Their first title track leans on familiarity rather than a sharply defined new identity.
A light funk callback rather than a new direction
The Bias List describes 12 o'clock as a light, funky dance song, and argues that it returns the duo to tried and true Seventeen territory. The review says it has been a while since listeners heard this kind of music from Seventeen members, so the familiar palette carries a sense of nostalgia.
That choice gives the track an easy likeability. The review calls it amiable and upbeat, and the overall impression is of a release that wants to comfort rather than confront. For a sub-unit arriving during a disrupted group schedule, that may be part of the appeal: it sounds like Seventeen even when Seventeen cannot appear as a full group.
The review also identifies a limitation. Jeonghan and Joshua are said to have quite similar vocal character, which makes 12 o'clock feel closer to a solo track than a duo showcase. The Bias List suggests that more textural variety would draw out the song's charms. The point is not that the voices clash, but that the pairing does not always create the contrast a duet might use.
The runtime becomes the main criticism
The strongest criticism in the review concerns length. 12 o'clock runs under two and a half minutes, and The Bias List argues that there is not much to the track within that time. The review says most of the song feels like the same highlight medley clip repeated, with no sense of progression and no meaningful endpoint.
That is a criticism about construction as much as duration. A short song can still feel complete if it uses its seconds to build, release and resolve. The review's complaint is that 12 o'clock spins its wheels, leaving the impression of a mood or concept rather than a fully developed song. The scorecard reflects a mixed response: Hooks 8, Production 8, Longevity 7 and Bias 8, for an overall rating of 7.75 and a grade of C+.
The Bias List also uses the track to raise a wider concern about ultra-short releases, arguing that HYBE appears to be one of the last agencies holding on to such lengths. That is the reviewer's opinion about a company-level tendency, not a measured claim about charts or streaming. Its relevance here is aesthetic: the review hears the short runtime as a disservice to the music.
Why Seventeen's sub-units carry extra weight now
Sub-units are a familiar way for K-pop groups to keep releasing music when a full-group schedule is not possible, and Seventeen's current situation gives that strategy extra weight. The Bias List ties the run of DxS, V8 and now JxJ directly to the group's inability to stage a full comeback while members complete military service.
For listeners, that changes how a release like 12 o'clock is received. It is not simply a new duo testing a sound; it is also a placeholder and a continuation. The review notes that the previous two acts occupied very specific sounds, while JxJ feel more flexible. That flexibility could be an advantage, allowing the duo to move between styles, but it also means their identity is less immediately fixed.
The nostalgic quality of 12 o'clock fits that in-between moment. The song is described as returning to a familiar Seventeen sound rather than pushing the group's catalogue somewhere unfamiliar. The review treats that as enough to work, even while questioning whether the track itself does enough.
A reader pushes back with a warmer reading
The review thread includes a contrasting response from a reader who rates the track 8.5. That comment praises the song for committing to its vision despite the short runtime and describes it as a Charlie Puth-esque funk sound with a stronger backbone as the chorus arrives. It also singles out a smooth, subtle breakdown and a final chorus that adds extra energy.
The same reader calls the track a sweet, comforting callback to early Seventeen and says the repeated "I'm so in love, so in love" lines felt slightly repetitive but did not spoil the overall impression. This is one listener's response, not a verdict on the wider fandom, but it usefully shows where the review's central objection can be read differently.
For that reader, brevity is part of the charm: the song is short and sweet rather than underdeveloped. For The Bias List, the same brevity is the problem. The disagreement is less about whether 12 o'clock is pleasant than about whether pleasantness is enough when a track leaves so little room for progression.
The short-song question is bigger than JxJ
The review uses 12 o'clock to reopen a recurring conversation about how short K-pop songs should be and what listeners should expect from them. The Bias List's position is clear: the track's length leaves it feeling like a sketch, and the review links that to an industry tendency it associates with HYBE. That argument is about craft and expectation, not a claim that every short song fails.
The reader comment offers the counterweight. A compact song can work as a mood piece, a burst of energy or a comfort listen, especially when the chorus lands and the production offers small details. The question is whether the listener wants a complete narrative arc or accepts a shorter, more repeatable format.
Because the source is a review rather than a chart report or an interview, it cannot settle that broader debate. What it does show is how quickly a runtime can become the defining issue in a release. For JxJ, the conversation around 12 o'clock is likely to be split between those who hear a charming callback and those who hear a song that ends before it has properly begun.
What 12 o'clock says about the sub-unit experiment
The review's portrait of JxJ is of a duo still defining their identity. DxS and V8 are described as having clearer stylistic lanes, while JxJ are presented as more of a grab bag. 12 o'clock chooses the safety of a familiar Seventeen sound, which gives the release an immediate connection to the group's past but does not yet establish a distinctive JxJ signature.
That is not necessarily a failure. A sub-unit debut can function as an introduction, especially when the parent group is not fully active. The review's mixed grade suggests that the song works as an amiable, nostalgic release but does not fully answer what Jeonghan and Joshua can do together that they cannot do apart. The similar vocal character noted in the review makes that question more pressing.
The practical significance is that Seventeen now have another active pairing during a period when a full-group comeback is not possible. Whether JxJ become a recurring unit with a clearer sound, or remain a one-off experiment within the sub-unit year, is not settled by this single title track.
The takeaway
12 o'clock is a light, funky and deliberately familiar addition to Seventeen's sub-unit run. The Bias List finds it amiable and nostalgic but too slight, pointing to its sub-two-and-a-half-minute runtime and repetition as reasons it feels more like a mood than a fully developed song. A warmer reader response shows that the same qualities can read as sweet and comforting rather than incomplete.
The release keeps Seventeen visible while the group cannot stage a full comeback, and it gives Jeonghan and Joshua a first shared title track. The open question is whether JxJ will build on that familiarity with a more distinctive identity, or whether 12 o'clock will remain a short, pleasant footnote in Seventeen's sub-unit era.