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Leen (リーン,Rīn?) is a 600-year-old fairy who also one of Touya Mochizuki's wife[10]. She was the tribal chief of the fairy tribe in Kingdom of Mismede[11][12] before becoming the court magician of Brunhild Dukedom[16] and the fifth queen of the Duchy. She currently lives with Touya and Paula at Brunhild Dukedom. Since she is married to Touya, she joins the Mochizuki family and her name becomes Leen Mochizuki (望月リーン,Mochizuki Rīn?). In addition, since she is the queen of Brunhild Dukedom, her name also becomes Leen Brunhild (リーン・ブリュンヒルド,Rīn・Brunhild?).
Leen is shown as a young woman despite her age, with silver twin-tails and gold eyes. Her young appearance is due to fairies maintaining a young appearance for their entire lives. However, Leen appears younger than the average fairy, something she greatly dislikes. She is usually wearing a lolita dress. The pin on the dress’s ribbon, the lines on its sleeves, and her necklace greatly resemble the astrological symbol of Mercury, reflecting a possible theme within Touya’s wives’ clothing.
Leen’s main personality trait is her tendency to do things out of spite. Touya has noted that she derives sadistic pleasure from doing so (For example, she smiled maliciously when she threw Kansuke Yamamoto’s jewel artifact into a wall, despite the former begging her not to do so.) However, Leen also possesses a strong thirst for knowledge. This can be seen in her enthusiasm for discovering all 9 Babylon flying structures. She is also quite perverted, as seen when she groped Tsubaki’s breasts while invisible and blames it on Touya.
She is first introduced in the series when her companion Paula brings Touya to her during a party in the Kingdom of Mismede which he was attending. Upon introducing herself (and vice versa) she asked how many magic attributes he possessed to which he admitted that he could use all of the magic attributes much to her surprise. She is again shocked when Touya explained that he could use every known Null Attribute Spell (a type of magic that can only be used by it's original wielder).
She tries to convince Touya to become her student by demonstrating her unique Null Magic (Program) to him, though she ultimately fails to convince him she is impressed when Touya manages to perform the same effect she did. (Programming a chair to move a certain distance by itself)
Leen first meets Touya after Paula leads him away from everyone else during his first time in Mismede. Leen initially wanted Touya to be her apprentice also, but he declined. Leen generally gets her way with Touya, whether it's making him read minds with Recall, making him open a gate to Eashen, or simply just teasing him. Later, she confessed her feelings to Touya and offered to be his 8th bride.
Charlotte is her apprentice, Leen gets told everything, sometimes even by force (above quote). Charlotte is fortunate to be her student, they both say since Charlotte can not defy her teacher. Charlotte is afraid to upset Leen and usually says she's 'joking' if she does it by mistake.
【Program】: this magic allows Leen to set rules toward inanimate objects which is similar with the computer programming. This magic can be added into the same object infinitely.
【Transfer】: this magic allows Leen to transfer her Mana to the appointed receptor.
【Protection】: this magic allows Leen to protect certain inanimate objects from physical degradation and prolongs its lifetime.
【Discovery】: this magic allows Leen to find the intended object only based on the exact parameter. Based on the certainty principle, her magic can not be used to find a slightly different object.
Appraisal (鑑定,Kantei?) - As a "Retainer" (眷属,Kenzoku?) of Touya Mochizuki, her magical item appraisal ability is sharpen and becoming her "Dependent Trait" (眷属特性,Kenzoku Tokusei?). [17].
Sacred Ring[19] - Leen received platinum gold ring from World God as wedding gift which was given through the great spirits. The ring is a sacred treasure which can act as receiver for Touya's divine power.
Quotes
"I can not believe this thing is actually happening in my live. That's what a longevity can do, huh?" - Leen before her wedding kiss[20].
Trivia
Leen wears the Mercury Astronomical Symbol on her dress, bow-tie, and umbrella.
Mercury Symbol on Leen's bow-tie.
Mercury Astronomical Symbol.
She possesses the most magic attributes among Touya's fiancees as well as most of the general populace except Professor Babylon and Touya.
She is the only known person in the world besides Touya who can use more then one Null Magic.
She is also the only known person in the world who has more then one original Null Magic.
She is currently Suu how to use light magic which is primarily healing spells as well as teaching Renne and Sakura as well.
