Taken too far

You woke up first. The blanket had come off in the night at least that's what you thought. Before you can open your eyes you hear a scream Cas had woken up next to you and was screaming. You sat right up with a jolt. In that second you noticed two things. Fistly stood over your bed, holding something large was Eden. Secondly, there was blood all over the sheets and your wife's lower body was missing!

"HOPE WHAT THE FUCK!!!!!" You shouted. You now see she was holding Cas's tail.

"It took a lot of effort but it was worth it. I reckoned if you refused to listen to reason I could save your soul. If your right-hand causes you to stumble, cut it off, and throw it away from you." Eden quoted a problematic bible verse.

"YOU APSOLUTE PHYCO!" Screamed Cas clutching at the stump of her lower torso. The wound was cauterised and num.

"Better to be married to half a human than to be married to half a fish." Eden said as if this was a sensible response. "It took a lot of effort, I had to use a pretty powerful numbing agent, salt water and a cauterising blade."

"You know those cauterising blades are made by demons right." You replied pointing out that using a demonic blade was actually sacrilegious unlike marrying a mermaid or other non-human. Some demons had asked for forgiveness and revived an official cleansing from the church in the 1800s. This gave them the ability to live in normal society and were just as good or evil as any other person. They now lived among people like all of the other creatures.

"Needs must." Eden replied.

"You hypocrite!" Cas screamed. "You should cut off your hand for the sin of using a demon blade. But I have a much better use for you. " Cas explained with a smirk.

"I will repent for my sins and the lord will forgive me." Eden said with certainty, a smug look on her face.

"Grab her honey." Cas snapped.

You quickly moved grabbing Eden causing her to drop the dismembered tail that was still dripping blood. The blade had cauterised most of the wounds but not all of them. By her feet was the blade, an empty water bottle and a large needle. You kicked the blade away.

"Bring her closer, sweetie. " Cas instructed. "Now, let me tell you some of my species' history. You probably know that before we got interrogated into human society we used to live only in the sea and lure human sailors onto rocks or tempt them into the water. You guessed correctly this was to eat them. However, you have no clue as to why. You see merpeople have very strong regenerative abilities. The ability to switch between a vestibule legs and a vestibule tail is a process that takes a lot of growth. We can use this fast cellular growth in other ways. However, this requires a lot of energy, like the energy from a whole person. When our people lured a sailor to their doom, we were taking them to a friend who had been injured, normally from a shark or rival tribe. "

"Just more proof that you are evil and your kind deserve to rot in hell." spat Eden as she tried to break from your grasp. "Now unhand me before I sue you for ****."

"You broke into my home and mutilated me." Cas spat.

"So take me to court. Saving Theo's soul from damnation is worth it." Eden replied.

"Oh, you're getting a much more biblical form of retribution," Cas replied. "Wernt you listening, I'm getting my tail back and your body is going to be the fuel for it, with no chance to repent beforehand." Cass explained as she lurched forward, rocking what was left of her body and launching it towards her. With your help, you stuffed Eden down Cas's throat. You kept shoving and Cas used her hands to pull aiding her throat muscles as she swallowed the troublesome neighbour down. It only took a few minutes to get her settled in Cas's stomach.

The rest of that day's plans were cancelled as you helped your wife simultaneously digesting Eden and regrowing her tail. She had transformed and used her legs to waddle down to the pool to transform back to her mermaid form to regenerate her tail.