A young woman named Ai finds herself stranded on the streets of Tokyo, Japan, in the middle of the night with no memories whatsoever. The only valuable item she has from her past is her beloved heart-shaped box. Penniless and hungry, Ai wanders the streets of Tokyo, trying to figure out how she ended up in this place. She soon meets an aspiring young rocker/musician named Kent, who shares her passion for music. She later finds work at a nightclub called Club Cupid, and from there on, her singing talent wins her a ticket to fame and fortune. But the life of a rich and famous rockstar diva isn't what it's cracked up to be. First talent agents, and later demons from her home world, seek out Ai to destroy her fame... and Ai herself.
- All There in the Manual: Important information like character motivations and such are only presented in the volume recaps. Which at times end up more interesting than the actual manga or make readers wonder if they read the same books as the recap writer.
- Brother–Sister Incest: Ai and Nora were lovers back on Ai-land. They're actually half siblings.
- Camp Gay: Hikaru fusses about, and squeals at, things like a 14-year-old girl, and has women's clothing.
- Clothing Damage: In the beginning, when Ai wakes up in an alley, her clothes are all torn and shredded.
- Freaky Fashion, Mild Mind: Ai has a very rock sense of style, but in the end she's soft at the heart despite her temper.
- Good Wings, Evil Wings: Ai has angelic-like wings and is considered the heroine of the series, while Tess and her two sisters have bat/dragon-like wings and is considered somewhat villainous, but that changes later on.
- Half-Human Hybrid: Ai is the result of her human father (Sei) and her Dougen/Angel mother (Zho).
- Love Triangle: Kent x Ai x Nora. Plus Hikaru, although he barely counts, merely having an unrequited crush on Kent.
- Meaningful Name: "Ai" means "love" in Japanese. Now, who came up with this manga, again?
- Rip Tailoring: Her first performance dress gets the treatment. Some of her later fashions look like they were created the same way.
- Self-Insert Fic: Courtney Love pretty much admits that the entire manga is a much more whimsical version of her own life.
- Shout-Out: Now, where have we heard about a "heart-shaped box" before...
- Winged Humanoid: Ai once she develops the wings.
- You Remind Me of X: Ai claims that Kent reminds her of Nora, a certain someone from Ai-land.