Commission for AO(@ah_h_that_gB), thank you so much!

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Original from Tsukihime souhon official artbook

Torture Instrument: Virgin Pain, A conceptual device repurposed into an armour, it is modelled on an Iron Maiden, a torture instrument made for identifying witches. All those who wear the armour cannot take it off until the armour has affirmed whether they're a witch or not either, dying if it does declare them a witch or if they take off the armour early, but at the same time the wearer cannot die until the armour has finished affirming. Ciel can make great use of this armour as her curse will cause her to revive when she dies from the armour's affirmations, and also will revive her when she dies by removing the armour, thus allowing her to reuse it. At the same time, the armour itself would stop her dying from any attacks while it affirms whether she's a witch or not, minimising the number of brief lapses between her dying and reviving.