Dr. Shuichiro Kudo is walking home one night when he saves a super-deformed angel named Kohaku caught in a tree by a crow. In return for its rescue, the angel offers to grant one wish. However, what does a man who has everything wish for? Thus, Kohaku decides to stay with Kudo until he decides on a wish, as well as complete its original mission of find the missing Angel Master of wind, Hisui.A four volume manga by CLAMP, it was animated in a short music video as well as recorded as a drama cd.If you were looking for the tropes involving wishes, see Make a Wish and Be Careful What You Wish For.
Calling The Angel Master Out: When Shuichiro and Kohaku finally find Hisui in the first volume, Shuichiro demands Hisui give Kohaku a proper explanation as to why she disappeared and why she refuses to return to heaven, saying that after all the trouble Kohaku went through, Hisui owes her student at least that much. Hisui complies.
Cannot Spit It Out: Though Kokuyo tries, he can't reveal that Shuichiro is destined to die soon as God continues to interrupt him.
Cats Are Mean: Played with in the case of Ruri and Hari; while they're Koryu's lackeys, they're technically Cat Girls and not all that mean.
Shinju is a much straighter example than Ruri or Hari. Every time he sees Shuichiro, he tries to bite him. Because he's in love with Kohaku as well, and considers Shuichiro his rival.
Celestial Deadline: Angels-in-training, like Kohaku, can assume an adult form during the day, but must be in a chibi form at night, while demons-in-training, like Koryu, can only assume their adult form during the night. If they fully master all magic, they can keep their adult forms all the time.
Crazy Jealous Guy: The Angel Master of Fire, Ryuuki, over Hisui. While he grows to accept that Hisui loves Kokuyo and wants to stay with him, he vows to hate Kokuyo forever.
And even then it's inconsistent at points - for instance, the Angel Master of Earth, Ransho, is given male pronouns, and the Angel Master of Fire actually bounces between the two genders on occasion. There's also Ruri and Hari, who are most definitely female demons.
God Is Evil: Subverted: God's punishment on Kohaku for leaving heaven is seen as amazingly harsh by all of the characters, until it is later revealed that this is to ensure his meeting with Shuichiro's reincarnation 100 years afterward. So...God Is Good, only verymysterious.
God also seems to accept the relationship between an Angel Master and the son of the Devil, at least by the end of the quartet.
Hair of Gold, Heart of Gold: Kohaku is the purest of all angel, good and innocence incarnated and has shimmering golden hair. Hisui is a downplayed version, as he has dirt-blonde hair in a few illustrations, to show that while good, Hisui's more mature and worldwise than the naive Kohaku.
Red String of Fate: This motif first showed when Hotaru rejects Shuichiro declaring she's not the person attached to the other side of his string. Later appears again when Shuichiro confesses his love for Kohaku, declaring her the person attached to his string.
Reincarnation Romance: God tries to avoid it by forbidding angels to fall for humans. When it happens anyway, he makes Kohaku sleep while bound to a tree so he can meet up with Shuichiro's reincarnation.
Red Herring: We find out lots of interesting things about Shuichiro's past; he has no parents, the woman who acted as his mother was a wisteria fairy and his grandfather eventually reveals he "just showed up one day, out of the blue" as a baby. Then there's the fact he looks a LOT like Kokuyo, the son of Satan, as everyone's quick to point out when the two first meet. So what's the big secret about Shuichiro, and why's it so important that God prevents Kokuyo from telling anyone? It turns out that...Shuichiro is a normal human and is destined to an early death. That's it.
Trademark Favorite Food: Milk and honey for Kohaku. Though it's not so much a favorite food as it is the only food he can consume, since all angels are forbidden to eat anything that once had life.
Tragic Keepsake: In the third volume Kohaku is forced to return to heaven, and Shuichiro is left behind with only one of the angel's earrings. He keeps it with him at all times after this, and is buried with it after he dies...allowing for his reincarnated self to possess it in the Distant Finale.
Truce Zone: The bridge between Heaven, Hell, and Earth.
Unishment: Hisui is stripped of her title as an Angel Master and banished to Earth. Since she and Kokuyo had eloped to Earth anyway, she's quite okay with this.
Strangely enough, Kohaku being stripped of all her powers turns out to be this as well - being powerless for the next hundred years means she will be able to spend that time sleeping, while waiting for Shuichiro's reincarnated soul to return.
What Is This Feeling?: Kohaku couldn't realize that she was feeling jealous for seeing Shuichiro's love for Hotaru since she never had felt jealous before.
Kouryu also had this reaction when he evaluated his unbridled glee at seeing Kohaku cry from his teasing.
Yamato Nadeshiko: Hisui. She wasn't voiced by Kikuko Inoue for nothing. After awakening, Kohaku tries to become one to help Hisui in homemaking.