[Mivereous]

Does using void related magic/skills put a strain/fatigue your body?

Rather then causing damage, we can just have it give a brief debuff to stats which would make your character not have to suffer an incurable ailment.

Using Void Magic excessively is the cause of Void Poisoning, which causes I think parts of your body to fall out into the Void, so I would think so.

It isn't about causing damage, it's about a debuff, yes.

http://sl2.wikia.com/wiki/Afflictions_System

I haven't actually had the chance to play around with the Afflictions System, so I can't comment on likeness to anything else, but I think what Shujin said makes sense.