He could see that Genis still seemed worried, but as to what he was worried about--for the Exsphere, for his sister, for the host? He was still worried for the host?

Mithos let out a small sigh, but still patiently answered the question. "What he feels when he wakes up will depend on the Exsphere. Some may experience some pain or fatigue with a regular Exsphere, but those feelings aren't severe." Otherwise, the torture and hard labour to which the prisoners were subjected wouldn't be necessary to feed the Exsphere. What sensations the Exsphere generated alone just wasn't enough.

But who could say what would happen with the broken Exsphere?