Mochita is an alien who travels to Earth in order to conquer that planet but the first person he bumps with is Issei, who already has some aliens at his house. Will this meeting with Issei change Mochita's plans?
侵略の為に地球に降り立った地球外生命体「もち太」。趣味で宇宙人を保護している高校生・一星に拾われ、もち太と他の宇宙人たちとのおかしな共同生活が始まった…果たしてもち太は無事に地球を侵略できるのか!?