There's not enough good slime/slime girl possession content out there, and animated scenes of this are rare as diamonds, glad to see it well implemented here.
Just a heads up, found a bug, if you activate the mansion mission, but never set foot in the mansion, yet try to continue Sapphire's story arc on that monday evening after beating the sewer dungeon, the double possession Victoria scene will play where she asks you to introduce her to sapphire even though you've never met Victoria.
Great scene even if I'd like to see it animated one day, but it didn't make sense since I hadn't actually entered the mansion and Emma hadn't met her yet.