If you're a free player, it's better to save your coupons that scrolls if you're very very determined to get a certain ninja. Asuma WB is in events for relatively cheap from time to time - seal scrolls are very random. I'm a paying player and it took me over 900 seal scrolls to get a regular rare in kage (onoki).

B/S that its better to save coupons or Onoki was a *?XD

Or what you mean is that you got onoki for the first time at your 900 seal ?

This, I have Susano - I've done ~1400 draws in Kage. Got onoki around 900-1000 for the first time