Board Thread:General Discussion/@comment-5283694-20130918011231/@comment-4188031-20140219220259

2.100.200.50 wrote: Didn't Lelouch get his memories altered when he was a kid, since his memory of his mother's "death" include seeing Nunnally under their mother, so wouldn't that mean it has already been confirmed that Charles can use his Geass on people more than once? No, his memories weren't altered then; he did witness what he thought was Marianne being assassinated but it was actually a decoy set by V.V.

As for Charles' geass, since a limit is never stated, it can be assumed he can use his geass more than once on one person