That Time I Got Reincarnated as a Slime Season 4: The 'Buff Rimuru' Meme, Explained

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.

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.

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.

• “However you look at it, that's obviously AI.”👍23⇄AIだろどう見ても— @煌龍フュリア · 👍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⇄ジョセフ・テンペスト— @しゅん-c8h · 👍371
• “Nah, Jonathan's actually the more jacked Joestar, so shouldn't it be Jonathan?”👍33⇄ジョナサンの方が筋肉あるからジョナサンじゃない？— @たけのこ0811 · 👍33
• “Brolimu, lmao.”👍2⇄ブロリムル草— @ユリリア-1234 · 👍2
• “Dragon Ball already proved "buffer equals stronger" doesn't work — that's what the whole Cell Saga was about.”⇄ムキムキが強さはドラゴンボールではセル編で失敗している。— @skyshk4649v
• “This thumbnail is giving straight-up "Gon snapping" energy.”⇄ゴンがキレた時みたいなサムネ— @シンハジメ

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.

• “Paraphrasing the other side's position: "Sure, we'll let you join us — but monsters don't get rights, myon~"”⇄相手側意見「仲間に入れてやるけど、魔物に人権はないみょ〜ん」— @ミーシャ-o3w
• “Honestly? He was right to lose it.”👍50⇄あれはキレて正解。— @まいか-o6o · 👍50

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.

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.

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.