Gan Gan Ganko-chan

がん がん がんこちゃん

Follows a boy named Gen who time travels from the year 2020 to a distant future where humanity has gone extinct. He begins staying at the Ganko family home in the Rustling Forest, where he has none of the amenities he is used to: no electricity, gas, or running water, as well as no television, smartphones, convenience stores, snacks, or games.