Duchess Lily is one of the older members of her generation, a graduate of Ohtori and Panopticon and former Master of the Revels of Amber. Lily was very shy and repressed as a child, and very studious. Now she's quite outgoing and friendly, and dresses in a rather risque manner which gets her the attention she seems to want. She is generally about as daring as she can get away with, although she does seem to have a keen sense as to who to flirt with and who not to.
She has her mother's knack for water magics, and is a skillful sorceress and shapeshifter. She's also known to be a crack shot with a crossbow and to have an extensive knowledge of the latest fashions and of shadow. And she's a logrus master; a rare trait in Amber.
Lily spends a lot of time trying to keep her younger sister out of trouble, when not sharing in that trouble. She gets along well with most people, although Sensei Haruna hates her for no apparent reason, though it probably is simply the Haruna-Yumi feud carrying over. She is on good terms with both of her parents, and likes to tease Keitaro.
Lily's heroic deeds during the Herald Crisis are too numerous to mention, but can be found in the UnS Timeline.
Since the Crisis, she's married Beowulf, attended Panopticon University (getting a Bachelor's and a Masters of Museum Administration), and now helps to run the Museum of Shadow, when not busy running off into shadow with Beowulf. She dotes on her son to a level which can kill those of low sugar tolerance. She remains close to her parents, her sister Mitsune, and to her new sisters Violet and Yomiko(who she helped train in magic), both of whom she approves of tremendously, though Violet seems less fond of her. Lily is known to be quite fond of her nephew Miroku, though she periodically lectures him on self-control. Nanbara aggravates her, and she seems to disapprove of Kanako on general principles. She helped train Deirdre in magic. Despite Naru's disapproval of her fashion sense, Lily and Naru spend a fair amount of time in scholarly discussion these days. Though she doesn't see her much, she gets along very well with Minako, and is known to dislike Ota Minor, considering him a thug. The same can be said of Captain Uotani, who has been known to assert that she thinks Bust Rimururu is Lily in disguise. Or possibly vice versa.