Milk Closet (2000)

Many children mysteriously disappear in 2005. This is called it the ‘Reasal Phenomenon.’ A few children came back with tails on their behinds. One of them was Hana Yamaguchi. Hana calls upon children with tails and creates the ‘Macro Cosmic Invincible Legion of Kids.’ These children can go freely back and forth from one world to another and with such special powers, they save missing children. But then, the Ali Troops invade this world. This is a fascinating SF drama about the wonders of the universe.

Source: www.anisearch.com/manga/1632