Out of CharacterBacktagging: Yes
Threadhopping: Yes
Fourthwalling: No
Offensive subjects: Nothing above a PG-13 rating.
In-characterHugging: They are not fans of touching in general, but the normal Yugi takes it a whole lot better than his other self. Both are more likely to pull away from an embrace if they don't know the person. Other than that, it's fine.
Kissing: He won't know what to do afterward, but go ahead.
Flirting: This is the fastest way to embarrass Yugi. The other Yugi won't acknowledge it unless it's
very blatant.
Fighting: Yugi doesn't fight, and will try to avoid it at any cost.
Injuring: Minor injuries are fine; anything major that could send him to a hospital should be discussed with me.
Killing: Not without permission. You may contact me through private message if you wish to discuss the possibility of their death. I am not against the idea, but I need to know ahead of time.
Telepathy/mind reading abilities: Not without permission. Again, you may contact me through private message.