After Kurumi (in demon possesion) attacks the academy base, the damage is fatal. So in order to stop Kurumi, all the steel angels drain themselves to the point of de-activation to power the ultimate weapon to stop Kurumi’s destructive powers.
steel-angel-kurumi-ep-23Steel Angel Kurumi Season 1 Episode 23
Steel Angel Kurumi Season 1 Episode 23
Crime and Punishment
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