User blog comment:Xilinoc/Ch. 579 - THE UNDEAD 6/@comment-2211792-20140509034915

No surprise Kenpachi is so anxious. The sole reason he returned on the battlefield is because he sensed Yachiru's reiatsu drop when Gremmy attacked her. And Yachiru herself said to Nnoitra that if he tries to hurt her, Kenpachi will go apeshit. The bond between the two is one of the strongest in this series.