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That Time I Got Reincarnated as a Slime: Japanese Fans React to "Buff Rimuru" — "What Is This Absolutely Jacked Slime?!"

「ムキムキリムル」のミームに対する日本のファンの反応(転生したらスライムだった件)

That Time I Got Reincarnated as a Slime: Japanese Fans React to "Buff Rimuru" — "What Is This Absolutely Jacked Slime?!"

On a Japanese reaction clip about a fresh Season 4 outburst from Rimuru Tempest in That Time I Got Reincarnated as a Slime, an exaggerated "jacked" thumbnail hijacked the discussion — the top comment, "What IS this absolutely jacked slime?!", pulled in 1,387 likes out of 267 comments total, more attention than the actual meltdown it was supposed to be about. Commenters spent the thread arguing over where the muscular art came from (guesses ranged from AI to just an artist having fun) and piling on comparisons to JoJo's Bizarre Adventure, Dragon Ball, and Hunter x Hunter, while others dug into why the scene itself — a council official dismissing monsters as rightless — was enough to make even easygoing Rimuru snap. By the end, someone who'd actually watched the episode showed up to point out Rimuru isn't drawn anywhere near that jacked on screen — a detail the rest of the thread was having entirely too much fun to care about.

This titleJapanese reactions to That Time I Got Reincarnated as a SlimeRead all 2 roundups on the title page
The official Season 4 PV for That Time I Got Reincarnated as a Slime. The reaction clip discussed below covers a different scene — Rimuru's meltdown at a council meeting, better known online for its exaggerated "jacked" thumbnail than for the scene itself. YouTube · isekai channel @バンダイナムコフィルムワークス (official)

Rimuru Tempest is built to look harmless. He's a slime wearing the body of a small, soft-featured demon lord, and half the fun of That Time I Got Reincarnated as a Slime is that world-ending power keeps showing up in the least threatening package possible. So when a Japanese reaction channel dropped a clip titled, roughly, "Breaking: the newest Season 4 Rimuru meltdown is going viral as an instant-punchline gag," nobody expected the real story to be the thumbnail — Rimuru mid-rage, drawn with a bodybuilder's physique he does not have anywhere in the actual show.

What IS this absolutely jacked slime?!

なんだ、このムキッムキのスライムは!

@コメ活をする神社公式ch1,387 likes

That thumbnail alone pulled in more attention than the meltdown it was supposed to be advertising. The top comment on the whole video is just five words of pure confusion, and it out-liked every other comment by a wide margin. From there, the thread split into two conversations running at once — one about a scene that actually aired, and one about a picture that clearly didn't.

Whoever drew the first buff Rimuru, I need to know your name, lol

誰だよ最初のムキムキリムル描いたやつww

@Taiseihoukan-w8o1,023 likes
  • However you look at it, that's obviously AI.👍23

Nobody claimed credit for the art, and nobody could agree on where it came from either — a few guessed AI, though the debate never got past vibes. What everyone could agree on was that once "buff Rimuru" existed, the internet was contractually obligated to compare him to every other anime character who's ever bulked up out of nowhere.

  • Joseph Tempest.👍371
  • Nah, Jonathan's actually the more jacked Joestar, so shouldn't it be Jonathan?👍33
  • Brolimu, lmao.👍2
  • Dragon Ball already proved "buffer equals stronger" doesn't work — that's what the whole Cell Saga was about.
  • This thumbnail is giving straight-up "Gon snapping" energy.

Underneath the muscle jokes, a decent chunk of the thread actually wanted to talk about why Rimuru snapped in the first place. The scene comes out of a council meeting where a human official brushes monsters off as not deserving rights, and that kind of casual condescension is apparently what finally got to him — Rimuru, who spends most of the show being aggressively laid-back, hits a nerve he can't just shrug off. Someone was already writing the sequel in their head, and it did not look good for him.

I can already hear Hinata going, "You tell ME not to lose my temper, and then YOU go and lose yours? ...sigh."

ヒナタ「私にはキレるなって言っといて自分がキレるとか、はぁ、」ってなってそうw

@とんだよv142 likes
  • Paraphrasing the other side's position: "Sure, we'll let you join us — but monsters don't get rights, myon~"
  • Honestly? He was right to lose it.👍50
The source material sells the "usually-chill nerd who turns terrifying the second you step on his landmine" trope without it ever feeling forced, and the anime's direction sold it even harder. Slime isn't just power-fantasy wish fulfillment — the way it captures "mild-mannered guy suddenly radiating menace the instant you hit his trigger" is weirdly, specifically real.

「普段は優しいけどキレたら怖いタイプのオタク」を、あそこまで違和感なく物語として成立させた原作と、さらにアニメーションで説得力持たせた制作陣の解像度が高すぎる。 転スラって 、ただの俺TUEEEじゃなくて「温厚そうなオタクが自分の地雷踏まれた瞬間だけ急に圧出してくる怖さ」の描写だけ妙に生々しいんだよな

@akea-xc1mg0 likes

Not everyone was fully on board with the outrage, or the muscle, for that matter. Deep in the replies, someone who'd actually sat through the episode showed up with a bit of a buzzkill.

I actually watched it — he's not jacked at all.

見たけどムキムキじゃない

@小役丸莉仁朗0 likes

Which tracks with the clip's own title, honestly, which billed the whole meltdown as an "instant-punchline gag" from the start — and at least one commenter thought even that description was generous.

It resolves so fast it's basically a two-panel gag at this point, lol

早すぎてもはや即落ち2コマやんw

@五月が好き0 likes

The thumbnail lied, the internet ran with it anyway, and the guy who actually watched the episode still can't get anyone to listen. That's Season 4 in a nutshell — and if the comment section has anything to say about it, they wouldn't have it any other way.

FAQ

Is the muscular "jacked Rimuru" picture actually from the anime?
No. A commenter who'd watched the episode said flatly that Rimuru isn't drawn anywhere near that jacked on screen. The buff image is a meme edit built for the reaction video's thumbnail, and the thread never settled on whether it was AI-generated or hand-drawn.
What actually made Rimuru snap in this scene?
According to the discussion, a council official dismissed monsters as not having rights — the kind of casual condescension that finally cracked Rimuru's usually laid-back demeanor.
Which characters did fans compare "Buff Rimuru" to?
The thread reached for JoJo's Bizarre Adventure (nicknaming him "Joseph Tempest," with a rebuttal that Jonathan is actually the more jacked Joestar), a Dragon Ball jab about the Cell Saga already disproving "buffer equals stronger," Hunter x Hunter's Gon mid-rage, and the portmanteau "Brolimu" for the Broly comparison.
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