backtagging: yes
threadjacking: ask first
fourthwalling: ask first
offensive subjects: yes (come on harry is a ball of offensive subjects)
hugging this character: yes
kissing this character: yes
flirting with this character: yes
fighting with this character: yes (not that he'll put up much of a fight)
injuring this character (include limits and severity): yes (but ask first)
killing this character: YES (but ask first)
using telepathy/mind reading abilities on this character: yes (but ask first)