"Hey you two, dinner!" Arthur shouted at the siren twins, who were in the crows nest. They had been up there for the last few days, refusing to come down. "Skraw!" "Shoo bird!" "Skraw!" a pelican began pestering Arthur about that time, "Go away!" it dropped a letter for him, "From the twins, read to everyone...ok?" 

"Arthur! Saved you a seat, Waddles was getting jumpy..." "Oink!" he sat down, "I got a letter from the twins" "What?" "No idea how they trained a pelican in three days but, it said to read it to everyone" "Speak! Im starving" Mike was getting annoyed. "Ok, lets see;"

"Dear Arthur, please read this to the triplets,

Your mother and i have been running for some time now, we sent Peeko to give this to you, we left you at the reef so we could lead the ones chasing us away, hopefully to be able to come back and get you six alive. We have reached a large trench, and have little time, please stay safe, and there is something else you four need to know, the twins, are not related to you four in any way, the ones chasing us are their real family, who were planning on killing them, or so we thought, they were going to kill prisoners, not them, but we have no way of turning them back, please, keep them safe, 

Dad~"

The table was silent. "Wait, WHAT?!" "So, they were human?" "And the pelican has a name?" "Are our parents even still alive?" "I dont know, but this is why those two are so upset, they couldnt handle this!" Bill looked up, "Have you checked on them?" "No, why...oh god please no" Arthur got up and ran, climbing the mast, he got to the crows nest, the clothes were there, but not the amulets. "They are gone..."

A few days have passed, they landed at an island, "Arthur, you may want to see this" "Hm?" "Look..." an amulet lay on the shore, destroyed, covered in blood. "No..." a scream was heard, "ARTHUR!" Arthur ran, the twins were sirens, but, they wernt themselves. They were angry, and had taken the form sirens take when they hunt, terrifying sea monsters. 

"We trusted you!" "You lied to us!" "WHERE IS OUR REAL FAMILY!?" the two were clawing at the sand, trying to reach Bill, who was protecting Dipper, who was protecting Mabel, who was protecting Waddles, who was eating a banana. "WHY WOULD WE KNOW?!" "Your gonna find out!" their tails quivered, and split into scaled legs, their whole bodies consisted of scales, both twins now could walk, "Calm down!" Heather looked at Arthur, then back at Bill, but shifted her eyes to Mabel. "You humans took us from our families, now its your turn" 

Quicker than lightning, Heather and Oliver grabbed Dipper, leaving Mabel and Bill. "LET GO!" their legs shifted into tails as they dragged him into the water, far enough out that rescue was not an option. "Dont kill him!" Oliver laughed, "Who said she was going to KILL him, no no no, we are going to take him, from his family and friends, with no memories of ether" "No! Please!" Dipper had stopped struggling, mainly because he was to scared to move. 

Oliver grabbed an amulet, and put it around Dipper's neck, changing him back into a siren, then they dragged him under. "PINE TREE!" "DIPPER!" Bill collapsed onto the sand, "No..."