Yeah, I think the only way to contain Mashiro's lust is through their combined efforts. He needs to date them both. It's the only way, Oosagi. Without Emma around to take aggro, you'll just get eaten alive, my man.
Alternatively, Emma could be convinced to also date Mashiro, but so far, that seems more difficult.
Alternatively, Emma could be convinced to also date Mashiro, but so far, that seems more difficult.