Disclaimer: I do not own OUAT. Darn.

Written for Day One of Swan Queen Week on Tumblr. The prompt was 'Magical Intoxication'.

They were all gathered on the deck of the Jolly Rodger. Finally, after seven days of sailing they were approaching Neverland and Hook was preparing to tell them about the dangers they would inevitably come up against. He told them about the fairies, which were nothing like the nuns Emma had become used to. They were a different sort of fairy. They were carnivorous with sharp little teeth and Hook most certainly had a few stories about them eating children and pirates. The shadows were another problem, not because like Pan's shadows they could wander around and hurt you but because Pan's shadow used them much like Regina had used reflective surfaces. They were a way to easily collect information from across Neverland but Pan was restricted by the fact that his shadow could only move so fast. Still, they needed to look out for the shadows.

Hook started to talk about something else but Regina's attention waivered. She could hear the song, just beyond the hearing range of everyone else on the ship. The sound of soft humming, a melody that her father had hummed to her. It was a secret that he had kept from Cora, his true heritage that gave him certain powers, even if they were dramatically weakened by him being male. Henry was the son produced from a mating between a Siren who had long ago been banished back to Neverland and King Xavier. Sons of Sirens didn't have the same abilities, but in Regina they had fully formed and for the first time in her life she would meet her sisters. Magic flowed through her, bubbling through her veins and igniting urges to do what came naturally to her. She'd never felt like this before, even when she had gone bare backing riding with only Rocinante and Daniel for company. She felt freer than then, more in tune with herself and everything around her.

Regina zoned back into the conversation with a small smirk on her lips. Hook was blathering on about Sirens now. Oh, how little he knew.

"The Sirens in Neverland are Mermaids of a sort. They have the fishy tail and all that but while the Mermaids want to eat people all year round the Sirens only try to capture people once a month. It's called the Siren's Song, the time of the month when you'll hear them singing and men will be drawn to them. They don't always drown you, I've gotten a man back before. Once"

Charming puffed out his chest. "I've fought a Siren before."

Hook shook his head. "Not like this. The Sirens in Neverland are different than the sort back in the Enchanted Forest. They don't want to drown you, that's just the by-product of them mating with you. They're nice enough when there's no Siren Song. Good conversationalists, really. But they get …"

"Drunk." Rumpelstiltskin supplied. "The Siren's Song makes them act differently. They lose all inhibitions and tend to act completely on instinct. But we can't know when the Siren's Song is until we meet with the Sirens, so we don't need to worry just yet."

Regina shook her head at them and grinned to herself. Oh, they needed to worry because they were sailing straight towards the Sirens and it was most definitely time for the Siren's Song. She started humming to herself as she headed downstairs into the cabin she shared with Snow and Emma. This would be interesting.

/-/-/-/

Regina was dozing when Hook thumped down the stairs and into the cabin. She had felt the need to rest and hadn't fought it.

"Rise and shine, Your Majesty. We need you on deck."

Regina sat up and scowled at Hook.

"What for?"

"We're approaching the Sirens and they're singing. So you fine ladies get to have some fun trying us up until we pass."

Regina rolled her eyes but followed Hook up to the deck. Emma and Snow were already tying Charming to the centre mast and Rumpel was standing to the side looking sour about the fact that he was next. Regina was sure he had argued the fact that he was the Dark One and wouldn't need to be tied up but apparently he had lost the argument because as soon as Emma and Snow had finished with Charming they started on him. Regina nodded towards the mast.

"Come on Hook, let's have some fun."

Hook grinned at her and led them to the mast, handing Regina a length of rope.

"I'm going to assume you know how to tie a good knot?"

"Of course, pirate. What kind of Queen can't keep her enemies tied up? Or her bed partners, for that matter."

Snow stumbled a bit and Hook and Regina rolled their eyes. Prude. Regina had just tied Hook's wrists together and was working on the rope to tie his chest to the mast when he interrupted her.

"You're humming."

Regina pulled the ropes tighter and grinned. She hadn't realised she was but it was getting close to night fall and they were almost on the Sirens, so it wasn't much of a surprise. She flicked her eyes up to his and she knew the moment her eyes shifted from brown to silver from the shocked look on his face.

"You…"

Regina pressed a finger to Hook's lips.

"Shhhh." She reached down and twisted his hook, making it come loose in her hands. She reached above his head and slammed the point into the mast. "We wouldn't want you getting free now would we?"

"If you shipwreck the Jolly Rodger…"

"I won't, Hook. My interest isn't in you or your little ship."

She tightened the last rope and left Emma and Snow to check over all the knots as she headed to the bow to watch the waves crash against the ship. She started humming again.

/-/-/-/

It took another half hour for the gentle humming Regina had been hearing to turn into a full on song. A shiver of pleasure ran down her spin. It felt so right. A quiet 'oh' came from further down the ship and Regina turned to find that she wasn't the only one effect by the Siren's Song. Emma was effected in an entirely different way though.

She was staring straight ahead to where the Sirens sat on the rocks singing. Regina wasn't surprised at all. Hook probably should have mentioned that the Siren's Song worked on any who found the female form attractive, not just men. Hook and Charming were looking in the same direction. Regina couldn't see Rumpel, but if they had followed the plan he would be unconscious. Only tying up the Dark One and expecting rope to stop him getting what he wanted would have been foolish. Snow's attention was on Charming which was why she didn't see Emma start to move to the side of the ship. Regina grinned and for the first time ever opened her mouth and sang.

Regina's wordless song was what snapped Snow out of whatever moody place she had been in. She looked around the deck and froze when she saw Emma at the side of the ship, half climbing over the railing. Emma had stopped and was staring at Regina. It didn't take her long to climb off the rail and bolt across the ship to stand in front of Regina. Snow tried to grab Emma's wrist was Emma was far too quick. Regina reached out and slowly trailed a hand down Emma's cheek to cup her chin. Emma's eyes fluttered hut and Regina stopped singing. Snow was yelling at them but neither wanted to pay attention.

Emma Swan was completely in her thrall, and Regina wanted to mate. She needed to mate, and Emma had already proven to produce exceptional offspring. Regina pressed her lips to Emma's and Regina felt her magic flow through her and into Emma. Emma was useful, she needed to survive this and a Siren's kiss was a potent form of magic. Regina drew away from Emma and giggled. Emma grinned at the noise.

"You should laugh more. Your eyes are silver, they're pretty,"

Regina smiled. "Dear, sweet Emma Swan. Thank you. You have no idea what I'm going to do to you."

"I have a bit of a clue."

Well, that was certainly true; they had fallen into bed enough in the past for Emma to know all about her sexual prowess. But this time it was different. Regina grinned and slowly pushed Emma backwards until she was pressed flush against the railing. With a small shove Regina sent Emma overboard. Snow screamed but Regina didn't turn to the sound, she had a mate. Regina clambered over the railing and jumped into the water. She had a mate.

/-/-/-/

Emma groaned as she came to. She felt like she had the worst hangover in existence. Everything was kind of damp, but mostly Emma was warm so it wasn't too bad. She opened her eyes and closed them again quickly. It was bright.

"Oh good, you're awake. Regina will be pleased."

Emma opened her eyes again and found herself looking into the face of a blonde lady. The lady handed her a water skin and Emma greedily drank from it.

"Where is Regina?"

The lady pointed down to the water's edge and Emma turned just in time to see Regina's head bob out of the water followed by a deep purple tail. Regina dragged herself, tail and all up the beach until she was close to when Emma lay.

"Hello, Dear. Did you sleep well?"

Emma just stared at her. "You have a tail."

Regina looked down at the tail in question. It was deep purple with lighter purple and blue scales flecked through it.

"Yes, I do."

"It's pretty." Emma mumbled awkwardly.

Regina hummed in agreement as the skin on her back started to dry. With a bit of effort she pushed herself over, resting on her arms and allowing the sun to dry her front. Moving in the water as a Siren was a beautiful thing, but on land things got a bit awkward. Regina ignored Emma as she tried and failed to keep her eyes off of Regina's naked chest.

"So, uh why do I feel like I downed a bottle of vodka last night?"

Regina glanced at her and waved a hand making Emma's head feel much better.

"We were drunk on the Siren's Song for all intents and purposes. I suppose it's only natural that you would have a magical hangover seeing as you aren't a Siren."

As Regina's legs dried she could start to feel the scales recede back into her skin as her legs started to form.

"So, last night we…"

Regina glanced at the blonde Siren sitting next to Emma. She nodded and dashed for the water, submerging herself when it was deep enough and her tail grew.

"Yes, Emma. We mated last night, as it is my nature to do so."

"Can we … do that … again? Only I had kind of hoped that I would remember banging a Mermaid. I mean, how many people can brag about that?"

Regina grinned. This could prove to be an interesting evolution to their sex life. She placed a hand to her belly where their child was growing. She wouldn't worry Emma about that yet, not until after they had Henry back.

"Of course, my Dear. But you're the one explaining it to you mother."