Tsukiko Ketchum, formerly Tsukiko Tachibana, lived in the young justice world. One day she was about to jump off a rooftop and saw Mew, the mythical Pokémon known to have the genes of all Pokémon, being chased by crazy scientists who intend to use Mew for their selfish schemes. Tsukiko ended up bringing Mew with her and ran away from those scientists. As she was running, a bright light covered both her and Mew. The next thing she knew, she was reborn as an infant. Watch as she faces the challenges from her previous life and current life while finding happiness. This is the start of the journey of Tsukiko Ketchum.