Tokyo Mew Mew

Synopsis

While Ichigo Momomiya is on her first date with Masaya Aoyama, she is bathed in a strange light and sees herself being merged with a cat. Afterwards, she begins to display cat-like behaviors. The next day, Ichigo follows Masaya into a park, where a strange jellyfish-like creature takes over a rat's body, turning it into a monster. Ryou Shirogane saves Ichigo and gives her a power pendant allowing her to transform into Mew Ichigo. With her new powers, she defeats the monster, turning it back into a normal rat. Afterwards, Ryou refuses to explain what just occurred, so the newly arrived Keiichiro Akasaka offers to do so instead.

(Source: Wikipedia)