Guardian Dog (2005)

Kurosaka Kendo is just your normal highschool boy, who likes to skip cleaning duty. But Kendo’s peaceful life ends, when he one night meets an strange man. That man claims to be an alien and is in need of Kendo’s body to survive on earth. Now, Kendo must not only deal with alien now resting inside of him, but also with other aliens, who for some reason seem to be after him.

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