Card Captor Sakura

Cardcaptor Sakura begins when ten-year-old fourth grader Sakura Kinomoto accidentally releases a set of magical cards called Clow Cards from the Clow Book, created and named after half-English, half-Chinese sorcerer Clow Reed. Each card has its own personality and characteristics and can assume alternate forms when activated. The guardian Beast of the Seal Cerberus emerges from the book and tells her it is now her responsibility to retrieve the missing cards. As she finds each card, she battles its magical personification and defeats it to seal it away. Cerberus acts as her guide, while her best friend and second cousin Tomoyo Daidouji films her exploits and provides her with battle costumes. Sakura's older brother Toya Kinomoto watches over her, while pretending that he is unaware of what is going on.
A boy Sakura's age and descendant of Clow Reed, Syaoran Li, arrives from Hong Kong to recapture the cards himself, but finds his goal complicated as he comes to respect Sakura and begins aiding her instead. Once Sakura captures all the cards, she undergoes the Final Judgment, presided over by Yue, the cards' second guardian, who tests Sakura to determine if she is worthy of becoming the cards' true master. Yue is the true form of Yukito Tsukishiro, Sakura's crush and her brother's best friend. Sakura is aided by her teacher Kaho Mizuki, who was sent by Clow to ensure Sakura is able to pass the test, because he chose Sakura to be the cards' new master when he knew he was going to die. Sakura passes the test and becomes the new master of the Clow Cards.
Life for Sakura is initially peaceful until a boy Sakura's age, Eriol Hiiragizawa, transfers from England, which coincides with new disturbances occurring in Tomoeda. Suddenly unable to use the Clow Cards, Sakura transforms her wand and creates a new activation spell, which can transform a Clow Card into a Sakura Card. As strange events continue, Sakura gradually transforms each card into a Sakura Card, unaware the events are being caused by Eriol and two guardian-like creatures, Spinel Sun and Ruby Moon. Yue begins to grow weaker, because he requires magical support from Sakura, but her magic is not yet strong enough to sustain him. Toya gives all of his magical abilities to Yue in order to ensure Yukito does not die. Sakura eventually deals with the pain of Yukito's gentle rejection of her feelings, as he instead loves Toya. Syaoran consoles Sakura, while finding himself falling in love with her, but is unsure of how to tell her.
When only the Light and Dark Cards remain to be converted, which must be done together, Eriol reveals to Sakura he was behind all the strange events. After the cards are transformed, Eriol explains that he is half of the reincarnation of Clow Reed, with Sakura's father being the other half. Eriol, who has Clow's memories and magical abilities, aided Sakura in converting the cards so they would not lose their powers. Before returning to England, Eriol asks Sakura to split his magic between himself and her father, so that he will no longer be the most powerful magician in the world. Afterwards, Syaoran confesses his love to Sakura, but she is unsure how to respond. Sakura is hurt and upset when he tells her he is returning to Hong Kong, and comes to realize she loves him too after talking with her friends. She rushes to the airport to tell him and he promises to return when he has taken care of some things. One year later, Syaoran moves back to Tomoeda permanently.

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