If this sort of post has an actual name, it's not coming to mind, so it'll just be the Can-Gaignun-Touch-You-In-The-Mind permissions post.
The long version's in his stats meme
here, but basically one of Gaignun's special abilities as a genetically modded clone is 'the suggestive ability that controls the thoughts of another person.' It's similar to the Geass effect; the difference being that there's no limit to how many times he can use it on a person, and he carries it out not so much in terms of absolute commands as mere suggestions; e.g. saying "A walk in the park would be pleasant" instead of "Go take a walk in the park".
Now this ability has some pretty unpleasantly god-modding potential, and I don't want to step on anyone's toes! ICly, Gaignun doesn't use it often, and when he does it's just to give his natural powers of persuasion a little boost. But I can understand if players aren't comfortable with their characters getting nudged in their decisions by someone else.
So if you don't comment to this post, I'm assuming that you're not okay with the idea of Gaignun touching your character's brains in general. Depending on the IC situation, I might have to tag you on IRC or email anyway to ask your permission in 'special cases' (like Gaignun being under threat of murder or something), so I apologize in advance. >:
If you are okay with some/all of your characters being braintouched in general, however, do drop a comment. <3
ETA: Also, let me know if any of your characters have supernatural mental defenses or that sort of thing~