Based on the shounen manga by Fujiko Fujio. 
 
Note: Screened as a double feature with Doraemon: Nobita no Uchuu Kaitakushi.

Kaibutsu-kun and his companions, Dracula, Wolfman, and Franken, travel from Kaibutsu Land to the Human Realm, where they encounter and battle several monsters, mainly assassins from the demon group Demonish. 
(Source: Wikipedia)

Nobita has been having a weird dream about a boy named Roppel and his strange companion Chami traveling in space. By a twist of fate, he met them in person where it turns out that they are real and that they were being pursued in space, causing their space vehicle to malfunction, connecting the space vehicle itself with Nobita's room. They journeyed to Roppel's planet and amidst their enjoyment, Nobita and Doraemon pledged to help Roppel's planet free from their oppressors.
 
(Source: Anime News Network)

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