Ichiru knows that Zero has a lot of questions for him-- many of which he might be aware of and others not so much, given there's still a hole in his memories.

"You worry too much."

He replied softly closing his eyes, shifting his head to Zero's shoulder to hide the frustration that still lined his face at the thought of not remembering more, "It's frustrating."

Admittedly, he's being a little honest here. Probably due to his own state right now.