Peter Parker

Backtagging: Go for it!
Threadhopping: Perfectly fine, so long as it's not clearly marked "private" or something. Even then I might be down for it, but you should ask first.
Fourthwalling: He'll think your character's possibly insane and/or a total creep, but I don't particularly mind.
Offensive subjects (elaborate): Nothing particularly triggering here, just use a little common sense please.

Hugging this character: Go for it. He'll definitely not be expecting it though, it's not something he's used to.
Kissing this character: Doesn't bother me. Could bother / fluster him though.
Flirting with this character: Yeah this is something he's definitely not used to, expect stammering and shades of red you didn't know the human body could achieve.
Fighting with this character: He's a superhero, fighting's kind of in the job description. As Peter Parker though, he's more likely to avoid it than engage in it.
Injuring this character (include limits and severity): Check with me first. I'd probably be fine with it, but keep in mind Pete's got some wicked durability going for him.
Killing this character: Ask first. That means you too, Goblin
Using telepathy/mind reading abilities on this character: He has no natural defenses against it, but ask first. I don't really need anyone shouting "PETER PARKER IS SPIDER-MAN" from the rooftops, and in the event of someone trying mind-control, he does have some impressive willpower to contend with. Especially since he's already dealt with the Symbiote.