In short - share the fuck out of it. Tell everyone you can.
In long...
Ghost Harem is my passion project. Marketability is the absolute last thing I am concerned about as the creator. Not that it would be very marketable to begin with, since it's about a gay throuple, the wacky situations they find themselves in, and the weird sex they have (to be very reductive). There's not a whole lot of ways I could advertise the guys in a mainstream sense without compromising aspects of their story. Even if I could, funding that monetarily would be a consistent issue, since I don't have a whole lot of expendable income. What I want is for Ghost Harem to reach the people who need it most — that's why made a website that's free and accessible to anyone with an internet connection. If you bothered to take a look at this page — and are reading to this point — chances are you really care! And it would probably be safe to assume that the people you surround yourself with might care too. So what I'm saying is, tell them. For the low price of free you can support this comic by making other people aware of its existence, and getting them interested enough to want to check it out for themselves. I'll be making it either way, whether you want to give me your hard earned dabloons or not. From the bottom of my heart, it means so very much that you took time to be here. Thank you.
Oh, eventually. It's not my top priority at the moment, but I've sent some stuff to my friends. If there's a demand for it, it'll happen.
I don't have a particularly fancy system for accepting coin if you're intent to give it. Currently, I accept donations and commissions through my Ko-Fi page. To briefly go back to the previous section, Ghost Harem merch would be there first before it would be anywhere else.