There Are Alien Heroes in My Watch

Invasion of foreign civilization... Plumber grandpa is missing... I can transform into various alien bodies... —————— What does all this have to do with this watch? —————— Do plumbers really only know how to fix things? A beat-up RV is high-tech? Is there a monster in my watch? —————— Even if civilization invades in the future. Even if the last drop of blood is shed. I also want to protect the most important person to me! Protect the land of China and Kyushu this time I am the hero!