Quick answer — Lenny code fiction performed 1 anime theme, including "Key -bring it on, my Destiny-" from D.Gray-man HALLOW.
Lenny code fiction performed the anime theme songs "Key -bring it on, my Destiny-" (D.Gray-man HALLOW).
Lenny code fiction's first listed anime theme is "Key -bring it on, my Destiny-", the opening of D.Gray-man HALLOW.