Yep, every comment of every page of all three sites. Although I made a majority of my comments on ComicFury, since that was the site on which I first read the comic.

You aren't the first one to point out the obstacle transphobic parents can pose for someone who wants to buy this comic (at least one trans reader reported that their parents were monitoring their mail, and so they wouldn't be able to get the books without them finding out). Unfortunately, going digital won't necessarily solve your problem: if you are under 18, your dad could probably find out about any electronic purchase you make with a credit or debit card.

Nevertheless, digital sales could still open up new avenues for you to read it safely. For example, you might be able to get a friend you trust to buy the hypothetical PDF, and you could pay them back in cash. Then, your friend could send you the file, and keeping a PDF hidden from parents is a LOT easier than keeping a printed book hidden.

I hope you are able to get into a less hostile living environment in the nearish future.
Well, I finally did it. I caught up. Not just with the comic--I was caught up with the comic months ago. Today, I finished reading every comment on every page of the comic on all three websites!

Rain is one of the most inspiring comics I have read. But as wonderful as the comic itself is, I'm even more amazed at the community that sprung up around it. Getting to read the life stories of other people reading the comic and struggling with queer issues in their own lives incredible. There is no other comic I am aware of with such an open and vibrant fanbase.

On a semi-unrelated note:
I'm somewhat frustrated that the only format for purchasing the Rain books is print.
Gumroad is an online digital store aimed at independent artists and writers who can communicate directly with their fanbase. A lot of webcomic authors sell ebooks through Gumroad.
Hivemill is a webcomic-specific site that sells both ebooks and physical merchandise for webcomics by independant creators. It even has a section specifically for queer-focused comics.

There are of course other ways for webcomic creators to sell ebooks, but those two sites seem to be the easiest.
So...any chance we could see PDF versions of the Rain books? I tend to move a lot, and so bringing printed books with me from one home to another is hard. But I do have money to spend on Rain, if you are ever able to sell the books digitally. I know that making a PDF out of an existing book requires a nonzero amount of work, but I know there are Rain Beaus who would gladly pay for a PDF version of the compilations.

And yea, it is possible for someone to just download all the individual pages of the online comic, but if I do that, then you don't get my money, and I don't get to read chapters A through D :(