Site cert is down indefinitely. I don't manage the server directly, only source code.
Use http:// if you want to access the site (eg http://waifusims.com/Manga/Hakoiri/Buy ).
Most of browsers will automatically use https://, especially if you've been on the site while the cert was alive.
Sorry for the late upload, it's automatically released on the site at the specified time now so I kinda pushed and forgot (also busy).