Haha, Proto was right on the spot.
And yes, the entire interaction between Keima and Chihiro was very bittersweet. The bye bye makes it sound like Chihiro will never fulfill her unrequited love, though seeing as Keima is more compassionate toward Chihiro now, I'm still hopeful. I just cant wait to see how their future interactions will play out. And, I wonder if we are gonna have a nice boat chapter next. Like, the goddesses can't share Keima, and each ends up taking a piece of Keima... (the end).
As for the next story arc I wonder if all of the goddesses will end up going to Hell to fight the vintage, and Keima will be left on Earth to continue his conquering, since Keima couldn't do anything to help in Hell.