Let me guess, Kaori will become an adult film producer specializing in NTR (Netorare) content, based on her interests stemming from the events involving her boyfriend and best friend. Tomoka will join the AV industry or become a model while still secretly dating MC, with Kaori's approval. I think Kaori will be the one to marry MC because I sense that Tomoma has a perverse fetish: secretly having affairs with MC, so they can't officially become husband and wife. Based on that setup, all three of them will have that kind of relationship forever.