Rozen Maiden: Träumend is actually the second season of Rozen Maiden.
In a nutshell, a powerful mage named Rozen from the 18th century (revealed in the manga as Count of St Germain) constructed seven dolls and imbued them with a living soul known as the Rosa Mystica. Their mission is to battle each other in what is known as the Alice Game, the winner obtaining the loser's Rosa Mystica until the last one standing becomes Alice, a real girl of unmatched beauty and purity. To help them, it is expected they will acquire human partners that they can use as a power source for the unique weapons and tactics each one possesses, but it appears this is optional as some of the dolls appear to not have human partners.
The first six of seven dolls in their order of creation are:
- Kanaria (aka Canaria)
In Rozen Maiden: Träumend, it appears the seventh doll is Barasuishou, but she is actually a doll created by Rozen's jealous apprentice to steal all the Rosa Mystica of the Rozen maidens so she can become Alice herself and the apprentice can prove himself to be greater than his master.
The real seventh doll is Kirakishou who only appears for a few seconds at the end of the second season.
Rozen Maiden: Träumend is really not for the kiddies. Though it is very light and humorous, by Episode 7 the atmosphere takes a solid turn to the dark and the body count starts to rise with three of these gothic lolita dolls driven to kill the others within the Alice game while the other three desperately try to protect themselves and each other. Hinaichigo lost her Rosa Mystica in the first season and it catches up to her in the second season. Her death is an incredible tearjerker with its inevitability and its poignancy. Um ... let's just say that manly tears were shed and I'll never watch that episode again.
Sadly, I know of no attempts to wrap up the many loose ends of the series so the fate of Shinku and her remaining friends as well as the hint of a much happier ending will remain unborn.