Still isn't explicitly clear, but I assume Emi's the romantic foil to Soprano. Or, at least, the one who stands in her way as a 'protector' of Mirei, of sorts.
Which, doesn't seem like Mirei needs any help on that front, as reticent as she is already in the face of Soprano's advances. But a bit of multi-party tension is probably just what this needs to shake things up a bit.
Thanks for the continued TL work