Imanouchi (イマノウチ), or Ranta Imanouchi (今之内乱太, Imanouchi Ranta), is a shy AA character that randomly appears in a seemingly inactive thread and starts dancing. The name stems from “ima no uchi” (今の内) which roughly means “now's [the] time” or “without delay”.

When found, the traditional response is to post “I saw” (みたよ, mitayo), sometimes with a Jisaku Jien emote, or have Nurupo hit him with a hammer. At the time, 2channel boards were so fast-paced, users would say “If you aren't Gah'd¹⁾ by Nurupo within one hour, you're a God” (ぬるぽしてから１時間以内にｶﾞｯされなかったら神) and people started to retrofit this phrase sometime after that.

• Imanouchi speaks in half-width katakana, which is supposed to be a soft voice or whisper. For some reason, the common translation uses all caps which ignores the shyness component.
• His usual phrase upon entering threads is “daremoinai… sendensurunara imanouchi” (誰もいない…宣伝するなら今の内), translated as “nobody's here… now's my time to shine” in this article.
  • The term, “senden” (宣伝, lit. “spread [the] word”), is an unusual choice of words as it's the same word you'd use for “advertisement”, “promotion”, or “propaganda”. I'd have to presume that he means “spreading” or “showing up” based on the kanji's etymology. The common translation kinda guts the sentence and uses “I can dance now!” instead.
• It's rumored that Imanouchi was created on September 14, 2001,²⁾ but the issue with this is that the call-and-response pattern of responding with “mitayo” (みたよ) had already been established.
• “Ranta tan” (ﾗﾝﾀ ﾀﾝ) doesn't have any meaning, unless it's a corruption of “lantern” (ランタン, rantan).

• Mou konee yo! - A similar earless character.

• Imanouchi on the 2ch AA Illustration Wiki