Isabella Rosamaki My Hero Academia

Whimsicott more commonly known as the Cougar was one of the tailed beasts. Centuries of being regarded as a mindless monster and sought after as a tool for war caused whimsicott to hate humans. After being sealed into Isabella Rosamaki, whimsicott attempts to maintain its cynical perspective about the world, but with Isabella's insistence on treating it with respect, the Cougar overturns its hatred and willingly strives to use its power for the world's salvation.
whimsicott is a character in the Isabella series, and one of the Tailed Beasts, formerly sealed inside Isabella Rosamaki
Often regarded with fear and hate because of its power, whimsicott endured centuries of being sought after and as used as a weapon with many regarding it as a being that had no emotions or feelings. This in turn caused whimsicott to develop a strong, undying grudge against humanity and often fight his hosts for control of their bodies.
After being sealed into Isabella following its release from its previous host, Isabella's mother, Hanayuki Rosamaki, whimsicott again sought control of its host, occasionally succeeding in situations where Isabella was driven to the point of anger or rage. This allowed whimsicott to manifest itself and gave Isabella the ability to cause incredible damage while under whimsicott's influence.
However, in recent times, with Isabella having learnt to control whimsicott while treating it with respect, whimsicott overcame its hatred and resolved to help Isabella in regards to the two of them fighting together in the Fourth Shinobi World War
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