Karin-chan's Mysterious Ring - S1.E1

Hanazono Karin is a normal, depressed girl who is feeling lonely after losing her parents some time ago and after her cat "Shii-chan" had recently died. When at the cat's grave one night, a young boy named Kazune Kujyou approaches her, but she gets angry at him when he calls her a moron, punching him in the face for it. A few days later, Karin meets his cousin, a young girl named Himeka Kujyou and then the ring that her mother gave her begins to glow mysteriously.

Note: In the opening, the time was in the future. Karin and Suzune found a Seed of Chaos. After Kazune, Jin and Micchi transformed, they tried to destroy the Seed, but they couldn't destroy it. Rika told that their current power weren't enough to destroy the seed. Karin then transformed and prepared to do Love Evolution with Kazune, but Rika planted the Seed of Chaos into the Chronos Clock. The Chronos Clock became error, and sent Karin into her past.