The Demon Lord's Daughter

There's a reason Zangetsu did NOT want Ichigo to use Mugetsu. She would be vulnerable...like a HUMAN. They despaired and hated the Shinigami for being so incompetent in cleaning their damn mess. They hated Isshin for bringing the topic up. Ichigo suffered the symptoms of losing her powers and genuinely thought she would die. But really, be careful when you speak of regrets...