Shinsuke and Shakugan are staying with Jinka and Tama, but Shinsuke isn't learning much in the way of fighting skills. Instead, Shinsuke is left behind to do chores when Tama and Jinka are informed of trouble with a local katawara.  
Letter of challenge
رسالة تحدي
Kampf-
aufforderung
Carta de duelo
Carta de duelo
Lettera di sfida
Carta de Desafio
Приглашение
на испытание