Out of Character

Backtagging/Slow tagging: Always.
Threadjacking: Ask first but it generally isn't an issue
Breaking Forth Wall: I'd really rather not.
Triggering Subjects: When in doubt, ask? Chuck is a walking trigger himself so if you wish for me to tone down certain aspects of his unpleasantness, simply ask and I will do everything I can to accommodate.

In Character

Hugging: He's pretty hands off but you're welcome to try?
Kissing: See above. But he's not the most subtle of individuals so if he is digging you, you will probably know it.
Flirting: Be my guest. He might even reciprocate. Unless you are Becket in which case flirting by way of butting heads is very liable to happen.
Shipping: Ship away! We have no real canon say so either way about which team Chuck bats for. I tend to be very egalitarian and play him as a somewhat conflicted bisexual. I ship him with Raleigh and Mako equally. The only thing firmly off the table is Hansencest. Otherwise come at me bro.
Injuring Character: Be my guest though please talk to me about anything too egregious before hand.
Killing Character: Only if we talked about it first. Or yanno...canon
Mind Control/Reading: Go head but I would like to think his experience with the Drift would make him somewhat more aware of someone trying to rifle through his brain but feel free to let me know if that is not good for you!