Raisen (雷閃, らいせん) is a mascot of Studio Tiara.
From http://studiotiara.x.fc2.com/staff.html
[quote]
【 雷閃（らいせん） 】
コンテスト受賞を機に加入した２人目の看板娘で
やっぱり絵師のシュミがかなり出ている。
無口・無表情の年下系ハーフエルフ。[/quote]
[quote]Raisen
She is the second of the showgirls we enter to win contest awards. Like you'd expect, the artist's tastes really came out.
Taciturn. An expressionless, younger half-elf.[/quote]