It was an outing between you and Yoru at the aquarium, but you got entangled in a looping devil that left you two trapped in the aquarium

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After a while Yoru used his power to turn the aquarium into a weapon a spear, making the devil angry and reveal itself

"You seem angry let me give it back to you, TAKE IT!" Yoru smirk while said and he threw the spear at the devil, the spear pierced through, causing the devil to die on the spot