関連ワード:  why do cats arch their backs    why do cats arch their backs when you pet them    why do cats arch their backs when they're scared    why do cats arch their backs when threatened    why do cats arch their backs and walk sideways    why do cats arch their backs and run sideways    why do cats arch their backs and hop    why do cats arch their backs up    why do cats arch their backs when playing    why do cats arch their backs when you stroke them