Very good news! In less than 24 hours Twitter user ちゃかも(Chakamo) helped solve our mystery. Chakamo explains that Mendo and the others are imagining Ataru with the stereotypical characteristics of a money-lender who has come to collect Lum who was presented as collateral for a debt. The flashy kimono, thick glasses and gold teeth are all characteristics of a flashy money-lender showing off his wealth. With Lum as his collateral he can now take her as his own.
うる星やつらは文化的なユーモアと駄洒落に満ちており、その意味を理解する前に外国の聴衆に説明が必要なものもあります。 うる星やつらの漫画（Viz）とアニメ（Animeigo）のアメリカの出版社は、リリースに翻訳ノートを含めて、日本独特のジョークや特に1980年代のジョークにコンテキストを与えることに長けています。
しかし、漫画からの1つのジョークは、RumicWorldのウェブマスターにとって謎のままです。 マンガ第18巻、64ページで、諸星あたるは能楽マスクと厚めの眼鏡で飾られた着物を着て突然現れ、ラムと一緒に眠ろうとします。
（大きい画像はクリックしてください。左側が日本語、右側が英語です。）
アニメはまた、エピソード89 （ラムとあたる・二人だけの夜） の16:59あたりでこのシーンを適応させます（以下のビデオはその部分にキューイングする必要があります）。 あたるは同じ服を着ており、金色の歯も追加されています。
Urusei Yatsura is filled with cultural humor and puns, some of which require explanation for foreign audiences before their meaning can be understood. The American publishers of the Urusei Yatsura manga (Viz) and anime (Animeigo) have been good about including translation notes in their releases to give context to some jokes that are uniquely Japanese or were particularly 1980s in their context.
However, one joke from the manga has remained mysterious to the webmasters of Rumic World. In manga volume 18, page 64, Ataru suddenly appears wearing a kimono with Noh theatrical masks and thick glasses and tries to sleep with Lum.
(Click for full-size images. Japanese is on the left, English is on the right.)
The anime also adapts this scene in Episode 89 (Lum and Ataru, A Night Alone) around the 16:59 mark (the video below should queue to that portion). Ataru is dressed identically and has golden teeth as well.
