I don't think it needs a pseudo-incest tag - imo that should be reserved for siblings by marriage who have grown up together - or at least spent a long time together and they feel / act like siblings etc. These 2 became 'sisters' like a few weeks ago or whatever it is.
It's like if they were already a couple of several years then their parents got married - I don't see how it would be pseudo incest because they wouldn't feel or act at all like sisters, and it seems the same here.
last edited at Jan 9, 2017 11:46PM