What did Bill Kaulitz do with his charisma? With his over-the-top goth-pop vocals — and even more baroque hairspray-and-mascara styling — the 20-year-old singer has made this German band one of Europe's most popular and irresistible groups. But on Humanoid, he sounds strangely reduced. In part, it's a question of hooks: With the exception of "Hey You" and "World Behind My Wall," the album is melodically anemic and strangely low-key. Subtle is not a mode that suits Kaulitz — just check the coiffure.