Tsukuyomi: Moon Phase Special
Japanese title: 月詠 -MOON PHASE- おにいさま, ゆらゆらきらきらどんぶらこ これって, なーんだ?
Type: Special
Episodes: 1
Source: Manga
Genres: Avant Garde, Comedy, Slice of Life
Studios: Shaft
Duration: 23 min
Rating: PG-13 - Teens 13 or older

Omake Special from the final DVD volume. The Special storyline has very little to do with the original series outside of having some of the same characters, and has a completely different storyline which does not fit into anything which came before it.

(Source: AniDB)