"If Raizou were to die, I would cry." Since Kon is a Kami-sama, crying is a sign that he will turn back into a Hakushi. So he's saying he will die if Raizou were to die.
Raizou's reaction to when he understands this is pretty heartwarming too.
When Waki mocks Himi for never regaining his memories and being "fake" Genma tells him off in a surprisingly mature manner and proclaims that he wants no one else but Himi.
When Asari after dying rejects Rikiichi's offer to finally rest in peace and regains his memories of Shoui after revival when he shouldn't be able to all because of his love for Shoui.
The finale. after reminiscing about the past, and reliving the deaths of Rikiichi and Magane in his mind, Waki sees a vision of Rikiichi and speaks with him. Afterwards he opens his eyes alone but sees a flower petal in his fist. It gives him the courage to finally awaken Magane, with the hope that Magane would regain his memories as Asari had.