Corruption & Despair
While generally altruistic creatures, it is possible for lepitsunes to get corrupted by prolonged exposure to malicious emotions, such as if kept by people who intend to use their wishes for selfish, greedy purposes. Granting wishes against their will causes holes to begin burning in their wings as a result of their resistance, and renders them unable to fly until they recover, but if it gets too severe for their wings to heal, they'll become flightless forever. A flightless lepitsune will become extremely depressed and listless and if their desire to continue living is too weak, they will disintegrate into stardust. Lepitsunes captured for selfish intentions would as a result quickly waste away and die.
Those that survive such incidents, along with lepitsunes that have seen too much grief or suffering or anger, or those that encounter severe emotional shock such as loved ones passing away, usually become unstable or gain a negative outlook on life, growing more aggressive or wary and distrustful towards humans and fade/darken in colour together with a boost in their powers albeit lesser control over them. Dark lepitsunes don't necessarily become evil or anything, but rather disillusioned with the world and the wishes they hear, until eventually they stop caring and just begin to wreck the world in their own ways and ruin it with what they feel it deserves.
Those that survive such incidents, along with lepitsunes that have seen too much grief or suffering or anger, or those that encounter severe emotional shock such as loved ones passing away, usually become unstable or gain a negative outlook on life, growing more aggressive or wary and distrustful towards humans and fade/darken in colour together with a boost in their powers albeit lesser control over them. Dark lepitsunes don't necessarily become evil or anything, but rather disillusioned with the world and the wishes they hear, until eventually they stop caring and just begin to wreck the world in their own ways and ruin it with what they feel it deserves.