"Ah, here we go" Sophie announced as they reached a isle labelled merfolk. "we want mermaids though" Jade countered. "which are female merfolk like how girls and women are female humans or mankind" Sophie assured as she headed into the section. "I always assumed merfolk was a completely different creature entirely" Jade mumbled.
most of the mermaid tails in the isle were of the same set design, only differing in size and colour, even though almost the entire place was filled with them besides a section instead setup with seashell bras using seaweed for the straps with a small ribbon in front being where the knock for wearing them as opposed to the back like normal bras and bikini tops.
"ah, this should do me" Sophie announced as she collected a deep blue tail from the racks of hers' and Jade's sizes. "don't forget the seashell bra" Jade agreed. "You sure that isn't optional?" Sophie questioned. "Sophie we're 14. past the age going about bare chest is accepted" Jade assured as she collected for herself a emerald green tail before following her own advice and picking out a seashell bra the right size to cover her B cup chest. "oh alright" Sophie accepted as she picked up a seashell bra for C cups.
"mermaids I see" Lewis remarked at the choice. "yep. that's our choice" Jade assured. "strange for you though, aren't mermaids considered dark creatures in your culture" Lewis asked Jade. "I'm half Japanese from my mother but never actually stepped foot in Japan" Jade answered "by mindset i'm fully local". "just being safe" Lewis assured before getting to the transaction "alright. two mermaids at 400 each... that 8 hours each by calculating 50 per half hour". "WOW, that long?" Sophie questioned. "also if you leave early you'll be refunded by the hours unspent" Lewis added before explaining how the transformation went "once in a stall undress and place your clothes and belongings within the compartment opposite the door, get dressed into your costumes and in your cases sit down, then each of you say 'fac me ipso mihi somnium' and you will be transformed and taken to the zone of your costume". "thank you" Sophie and Jade returned as they headed off.
Eventually within the stall of their choice as they were getting dressed. "8 whole hours, how big of a deal is that" Sophie joyfully called out as she tied on her seashell bra. "well we are renting them as opposed to fully buying and rental prices are often smaller" Jade assured as she rolled her tail over her legs. "but they say actually buying costumes here costs trillions. in fractions-" Sophie started as she got to getting her own tail on. "most rentals your thinking of are by months, we're merely a few hours. by law we're not stiffing them" Jade insisted.
once both were dressed and seated on opposite ends of the stall "god these tails are tight" Sophie complained. "well yeah. I mean they are based on the types used by professional mermaid performers right down to the monofin" Jade pointed out. "even though they aren't actually used for such. still it's likely so as to maintain the illusion against magic haters" Sophie remarked before asking "anyway are you ready?". "put it this way" Jade answered, before both girls said in sync "fac me ipso mihi somnium".
suddenly both girls felt it and took pleasure as they felt the changes; their lungs altering to allow the metabolism of air from water, their eyes developing a protective invisible membrane against water stinging, their legs merging with the costume tails into a single limb each as their skeletons from their waist down changed from hip and leg bones to extended tailbones as the point at their waistline where the tails ended went from obvious costume gap to flawless transition from skin to scales.
"incredible. IT WORKED" Sophie called out in joy as she got up but quickly fell down. "can't stand now. tails can't support us like legs" Jade assured as she slowly got off her bench to get to the floor which both suddenly noticed was slowly getting flooded from the cracks in the door. "it'll take hours with the door shut" Sophie remarked as she crawled over and pulled herself up to the handle. "umm...Sophie I doubt-" Jade started as Sophie opened the door but as opposed to being deep under the ocean they were instead atop it. "must be like this to prevent those reverting from drowning" Sophie remarked as she dove in. "guess so" Jade agreed as she followed to begin their adventure: