Garfiel Tinsel is the former guardian of the Sanctuary and a member of the Emilia Camp. Introduced during Arc 4, he became one of the main supporting characters of the season. He's a half-beast human and Frederica Baumann's half-brother. He can transform himself in a giant golden tiger that can deal powerful attacks but with a cost of losing his reason, so he uses this ability when he's pushed to the limit
