Viola’s eyes went wide. She looked at Wave with an expression of stunned disbelief, realizing it had bound itself to her without telling her any of this, but Wave simply looked back at her with enormous, guileless eyes and said,

"That monster is jealous of our companionship and our world’s ways. I will protect you from werewolf monsters like him."

Viola pressed her fingers to her forehead. "First of all, he is not a monster. He is my husband, and you will treat him with respect if you want to remain near me. His name is Sebastian." She said firmly, and then asked, "Is it because you bound yourself to me that I can now understand you?"

Wave nodded.

"And will you assure my husband that you will not cross your boundaries and will not petition for a form to be my mate?" She asked, still finding the entire concept faintly absurd.

Wave looked at Sebastian with profound displeasure, then looked back at her and said, "That is not up to me, Mermaidia. I can only take a form if you wish it and choose me. Your wishes are my command."

"Then that is settled." She turned back to Sebastian. "You have nothing to worry about, it cannot take a form without my permission. Now can you both please stop glaring at each other so we can talk about why we summoned Wave here in the first place?"

Despite her words, Sebastian did not like this. He didn’t like that the creature was now connected to her. Not at all. The creature was bound to his wife, sharing feeling with her, and he had not yet marked her, and he deeply regretted suggesting they summon the thing. But Viola needed answers about her sister, and so he swallowed his possessive jealousy down and nodded.

"Ask it about your sister." He said, watching Wave with narrowed eyes. "Ask it if Ivy is in the sea."

Wave understood what Sebastian had said and turned to Viola. "I don’t know. I have never been with the other Mermaidia, my place is with you, and I go only where you go and protect you from harm. What I do know is that the sea witch has been trying to reach you, and I have been turning her away each time by blocking her portals." It paused, then bounced eagerly within Sebastian’s cage. "Is Wave not amazing, Mermaidia?!"

Viola’s eyes turned sad at the confirmation that Wave knew nothing about her sister’s fate and wouldn’t know what had happened to her after she was taken to the sea, but she smiled at it anyway.

"Yes, you are. Very amazing."

Then she asked more quietly, "Who is the Sea Witch?"

Wave stilled. When it spoke again, the playfulness was entirely gone from his gurgly voice that sounded like someone talking with a mouthful of water.

"She is wicked. She controls many Tidekin, and she wants you too. She is very dangerous, Mermaidia. Do not go into the sea. If you do, she will take you, and you will not come back. Scary. Very scary." It singsonged the words, curling into itself.

"Why does the Sea Witch want me?" Viola asked with a frown, feeling Wave’s fear in her chest, which made goosebumps rise on her skin.

"Don’t know. I don’t like the Sea Witch. She turns Tidekin into stone and keeps them in her very scary cave."

Viola exchanged a look with her husband, and she saw his eyes drop to her arms, where the goosebumps were obvious.

"You’re shivering, love," Sebastian mused as he swam closer and pulled her into his arms, holding her against him without her asking to be held. He saw that Wave was also trembling and realized the little shit was transmitting its fear to her, and he fought the urge to strangle it in its cage.

After speaking to Wave for a while, Viola came to understand that the entity that had dragged her under in Nightshade was none other than the sea witch, and without a doubt the same one who had spoken to Sebastian and tried to manipulate him. Wave told her,

"The Sea Witch is very good at manipulating. She can make even the smartest person believe her words. She has the greatest power and controls the sea. I am afraid of the Sea Witch."

---

"I believe she manipulated you into thinking I was one of the sea creatures and had come to destroy your world," Viola said, after they had left the pool room and spoken with Wave at length. She could see Wave trailing behind them in a thin path of water, flattening itself against the floor and blending in whenever Sebastian turned around.

Sebastian had been quietly taking everything in, and he couldn’t believe a sea witch had used her abilities to manipulate him that day, but now he understood why he had believed it so completely, believed it enough to almost destroy everything between them, right up until the moment he had seen his wife’s tears.

"I wonder why the sea witch is fixated on you specifically." Sebastian said thoughtfully as they walked, his hand around hers and tightening without him fully realizing it, because somewhere in the back of his mind, Miss Lara’s words were surfacing again. She had called the water creature the twins’ aunt. Could it be the sea witch then?

"I don’t know." Viola murmured. "But the deeper I look into all of this, the more I realize how much danger simply existing puts me in. It seems I am not truly safe in either world..."

"We can build a safe world for you right here beside me, sunshine. You belong where I am, and I will do everything in my power to keep you there." Sebastian said, and he meant every word of it.

Viola felt warmth move through her chest at his words and she hooked her arm through his, leaning her head against his shoulder and breathing in his scent. "Thank you for always having my back." She whispered. Then, after a small pause, "Can I have my second chocolate bar now?"

Sebastian reached into his trouser pocket and produced it for her without a word.

"What are we going to do about Wave?" She asked as they stepped into the elevator.

Sebastian’s brows pulled together. The more this little water creature kept coming up, and the fact that it was quietly following them right now, leaving a damp trail along the elevator wall, the more unpleased he felt about it.

"I think we should contain it somewhere before it exposes itself to someone who shouldn’t see it. We don’t—" He didn’t finish the sentence, because a splash of water dumped squarely over his head from the wall where Wave had been crawling.

"Don’t listen to the monster, Mermaidia!" Wave said, scuttling back toward Viola and leaving a trail of wet patches across the elevator floor. "May the Sea Goddess strike his mouth!"

"What is it saying?" Sebastian asked, wringing water from his silver hair with one hand.