芦江事件と呼ばれる湾岸区域で起きた怪事件。
事の発端は「海の上に怪獣がいる」という通報からだった。本来なら悪戯で処理されるような内容だが、 最初の報から10秒も経たない内に同じ地区から同様の通報が相次ぎ、2分後には回線はパンク状態になってしまう。
更に確認に向かわせた警邏からの報告も「巨大な生き物のようなモノがいる」という不明瞭なものばかりで、本部が観測機を飛ばしてその”怪獣”の映像を得たのは発生から20分後の事だった。
相手が巨大な上に正体も分からないので下手な手出しは出来ず、人間に出来る事と言えば精々周辺地区の交通整理位だった。
そして大勢の人間が見守る中、ソレはゆっくりと東に進み、30kmほど進んだ所で煙のように消えてしまった。
通報件数が多い割りには建物や船舶の被害報告は無く、直接の人的被害も皆無な為に、 これは生き物ではなく虹のような未確認の自然現象なのではないかとも言われている。
写真は記念撮影中に偶然撮られた1枚。カメラに収まりきらないほど大きなソレが写っている

They called the mysterious event that happened near the shore of the bay the Rokou Incident.
It began with a report: "There's a huge monster on the water!" It was a report that by all rights should have been treated like a prank, but before 10 seconds had passed identical reports began pouring in from across the area, and within two minutes the line had been broken up.
They were all garbled messages from patrols confirming the presence of a "giant thing that looked alive," and 20 minutes had passed since the initial report before headquarters was able to send out an observation plane and secure video footage of the "monster."
It was not only huge, but no one knew what it was, which meant the most mere humans could do was traffic control.
And so, with huge crowds monitoring it, the creature progressed slowly east, and after it had gone 30 kilometers it disappeared, as in a puff of smoke.
Though the number of sightings was high, there had been nearly no damage to buildings or ships, and because there had been no direct damage to humans, people began to wonder if it had been not a living creature but an unidentified natural phenomenon, like a rainbow.
This tourist photograph captured the giant by accident. It is too big even to fit into the frame.