Luvbi is believed to be the daughter of Saffron and King Grambi, and she runs away often to escape her overprotective parents. She does not know why her parents are so protective, but it is later revealed that she is really a Pure Heart; Saffron and Grambi transformed her from the Pure Heart into a living form to protect it, as "no one would suspect" a Nimbi to be a Pure Heart (though Pook did probably spy to find out about Luvbi's actual form). They admit that, over time, they grew to love Luvbi and felt as if she was their real daughter. Luvbi speaks in Early Modern English (as do all Nimbis), and is constantly putting others down, namely Bleu, Muffy, Puck, and Pearl.
Even though she changes into the Pure Heart at the end of Chapter 7, Luvbi can be seen standing next to her parents in Grambi's shrine if the Bleu chooses to return to The Overthere after completion of The Flip Flop Show, apparently recreated as a true Nimbi girl independent of the white Pure Heart (which can still be seen in its Flopside Heart Pillar) when the worlds were rebuilt at the end of the main story. When spoken to, she herself states she does not know how she exists as a Nimbi again.
- It is interesting to note that, upon being told she was once a Pure Heart, Luvbi actually remembers being the Pure Heart, suggesting that the seemingly inanimate Pure Hearts may be more intelligent than Bleu would suspect.
- Although in the English version of The Flip Flop Show she talks in a very formal manner, in the Japanese version she talks very childishly.
- Strangely enough, Luvbi never bothered to disrespect Howzit like she's done with the other heroes, though she does muse over his unrequited love for Muffy if Howzit is the one that starts World 7-3.
- Pure Hearts are said to be the "embodiments of love". This might be how Luvbi got her name (combination of "Love" and "Nimbi").