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[Gallery] Leen ( リーン Rīn ) ?
is one of
. She was the tribal chief of the fairy tribe
before becoming the court magician of
Brunhild Dukedom 
. She currently live with Touya and
Leen is shown as a young woman despite her age, with silver twin-tails and gold eyes. She is usually wearing a lolita dress.
She has a strong thirst for knowledge. This can be seen in her enthusiasm for discovering all 9 Babylon flying structures.
Leen was Charlotte's magic teacher in the past. She used borderline torturous methods to teach. She is also quite mischievous, groping Tsubaki while invisible and blaming it on Touya.
: 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.
【 Program】 : this magic allows Leen to transfer her Mana to the appointed receptor.
【 Transfer】 : this magic allows Leen to protect certain inanimate objects from physical degradation and prolongs its lifetime.
【 Protection】 : 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.
【 Discovery】 Appraisal ( - As a "FAMILY" 鑑定 Kantei ) ? ( of 眷属 Kenzoku ) ? Touya Mochizuki, her magical item appraisal ability is sharpen and becoming her "FAMILY TRAIT" (. 眷属特性 Kenzoku Tokusei ) ? .
Grimgerde - Leen's exclusive  Frame Gears which is a blitzkrieg assault type FG.
Sacred Ring - 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.
"I can not believe this thing is actually happen in my live. That's what a longevity can do, huh?" - Leen before her wedding kiss .
Web Novel Arc 18 Chapter #134, Leen told Touya about her age.
Web Novel Arc 29 Chapter #405, It has been two years since Touya met her. ↑
Web Novel Arc 6 Chapter #45, Touya described her appearance as a girl with white hair and gold colored eyes.
Web Novel Arc 22 Chapter #185, Leen has all magic affinity except Dark.
Web Novel Arc 6 Chapter #45, Leen showed her program null magic.
Web Novel Arc 5 Chapter #32, Touya learned transfer, a null magic that have been taught by Charlotte's master, Leen.
Web Novel Arc 6 Chapter #48, Leen told Touya about her protection null magic.
Web Novel Arc 24 Chapter #232, Leen told Touya about her discovery null magic. ↑
Web Novel Arc 31 Chapter #448, Leen married to Touya. ↑
Web Novel Arc 6 Chapter #45, Leen introduced herself as the chief of fairy tribe. ↑
Web Novel Arc 22 Chapter #184, Leen retired as the chief of fairy tribe.
Web Novel Arc 29 Chapter #389, Leen was the Mismede's court magician.
Web Novel Arc 7 Chapter #54, Leen decided to stay at Kingdom of Belfast as an ambassador.
Web Novel Arc 14 Chapter #103, Leen decided to stay at Brunhild Dukedom as an ambassador. ↑
Web Novel Arc 22 Chapter #184, Leen decided to become Brunhild's court magician.
↑ Web Novel Chapter 30 #442
Web Novel Arc 26 Chapter #255.
Web Novel Arc 31 Chapter #449. ↑
Web Novel Arc 31 Chapter #449.