Eternal Night, Starry River: My Husband and I Refuse to Be Cannon Fodder

I recently watched the TV series Yong Ye Xing He and got completely hooked. I especially, especially, especially love the water-demon couple.

But I feel sad about what the two of them went through, and hope to give them a happy ending in my story.

Note: I'll try not to make the main characters look bad, since I like them too.