As ShroudedLion said, we will not be implementing poly relationships mostly because we don't want it to be... "forced". Like how shipping between characters then inserting the Scriviner in that relationship, or vice versa.
Once we get a better idea of polycules, we might implement it, but with our current experience (both irl and in media), we are not ready to even dive into the thought yet.
Especially ships that are a bit more... risque