The operative words seem to be "invasion" and "violation." You don't consent to an invasion or a violation.
Or to put it another way, if you do consent, it isn't an invasion or a violation.
"The act" seems to refer to entry into another's mind. If "the act" only referred to "invasion" and "violation," it would be redundant and unnecessary for it to, effectively, say, "an invasion is always a violent invasion."
Consider a soul gaze. You are forced into it. You can't control it through any act of yours. You can't initiate one, only a Wizard can. Is that natural? It seems pretty invasive.
I have considered it. See before, where I posit and argue that soul stuff is fundamentally different from mind stuff -- hell, people share and spread their souls around
by accident. To my knowledge, nobody has been able to "accidentally" read someone else's mind.
We're quibbling over the word natural. A skull serves a purpose to protect the thing it surrounds. It exists because the thing inside of it can be damaged if it didn't. If there were no such threat they wouldn't have evolved. The phrase natural is a question begging term.
I don't see how all of that doesn't also apply to the mind. The game text makes it pretty clear that there is a fundamental barrier there -- it serves a purpose to protect the thing it surrounds (the mind). It exists because the thing inside of it (the mind) can be damaged if it didn't.
Not very, since in Changes he is pretty blase about her altering his mind. Just because he wanted to cheat Mab. If Micheal was ignorant of the risks, Harry certainly wasn't. Those who live in glass houses....
"Blasé" and "just because" are not terms I would use to characterize Harry having his apprentice blank out parts of his mind in pure desperation before he sells his soul to an evil faerie queen as a last resort before a mission that's only going to get more suicidal the longer it goes on.
He's not having her do it to forget a bad TV show he watched. He's doing it because he's going to kill himself. His alternative plan was literally joining up with a Fallen Angel from Hell. There is nothing "blasé" about that exchange. It's clearly presented as a last resort that he's only doing now because he feels there's no other choice.
But all of those quotes from the game use the same terms. Breaking in, invasion, violating. For the house analogy, what if someone gives you the key? The key in this case being permission. Unlocks the door.
And yet it says "no matter how gentle," and establishes right off the bat that there is a fundamental barrier that exists between one mind and the next.
The text effectively equates "crossing" with "invasion." The section on Psychomancy itself begins:
Practitioners that read and manipulate minds
are called psychomancers (or sometimes neuromancers).
Given that these acts violate the
Third and Fourth Laws of Magic, they may also
be called headless, thanks to the action of the
Wardens. Psychomancy is neither well documented
nor condoned, though it seems every
now and again some new wizard comes along
with a talent for it, trained or not. The Council
does its best to intercede as quickly as possible
in such cases.
No qualification there, no mention of "invasion." It just puts it plainly: Reading another's mind violates the Third Law.
The book describes reading dead folks' thoughts as grey but "mostly" safe, and that empathy is enhancing your
own ability to perceive, not reading into someone else's head.
The only straight-up, no-grey, legal psychomancy the write-up mentions is doing it on
yourself, for things like supercharging your brain, digging up your memory, etc., but adds it's very dangerous, noting, "Just because you’re doing it to yourself doesn’t make the act any less violent."