Aqua, and yep!

"Kazuma! You are being unfair! I need it!" Aqua protested, stomping her foot and puffing out her cheeks.

"Then find a way to pay for it!" He barked back. "I for one don't wanna sleep outside because you want some high quality booze!"

"Ugh, you have no respect. I am a goddess! You'd have me pay for my own booze!" she whined, crocodile tears forming in her eyes.

"I'll respect you when you do something worthy of it! Now shut it. I am trying to think," he replied as he rubbed his chin, trying to consider how to make more money to fund a decent lifestyle in this new world.

Aqua pouted and turned around in her grumpiness. Darkness was nearby but she seemed to be lost in her own thoughts. They had just got back from hunting some gross monsters and Darkness was likely recounting the experience joyfully. Megumin was resting in a room upstairs from using her Explosion magic on those frogs. A glint caught Aqua's eyes as she noticed a dusty golden ornate in the ground.

"Kazuma! Look! Gold! We can sell it for the wine. Grab it!"

Kazuma took a lazy glance at it. "That looks like crap. I'm not carrying it."

Aqua stomped her foot. "It is not! You think my divine sense would be so easily fooled!"

"Yes," Kazuma said staring at her with cold eyes.

Aqua storms over towards the trinket and picks it up. "You are worth a lot aren't you? More than just one bottle perhaps? Just need a little shine." As she rubs it, it gushes out blue smoke. "Eek! What the!?" she protested, before finding that the smoke actually had some kind of grip on her, and was dragging her to the spout of the lamp as she was pulled off her feet. "Kazuma! Help!"

"Omg, you freaking bimbo. Can you like not cause a problem for two hours!" Kazuma shouted in pure exasperation.

"Kazumaaaaaa!" Aqua pleaded/whined as she was drawn into the lamp, smoke and all.

With the smoke vanished. Just the golden trinket remained. "Oh my. What do you think happened to her... could it be, that there is some horrific monster inside? We must rescue her!" exclaimed Darkness as she ran up.

"That is exactly why we must not touch that thing! She is a goddess, I am sure she will be fine," Kazuma said, giving a careless shrug.

"Where is your honor Kazuma! We must not leave a comrade behind!" Darkness says with a large smile on her face.

"I don't think that is what is really motivating you," he deadpanned at her.

...

Meanwhile, inside the lamp, Aqua was undergoing an actually pleasant experience. She was floating among shimmering blue vapors, her clothes vanishing into said mist as it caressed her body in ways she had never been touched before. It felt so good, and she felt her panic somewhat ebb away. "Okay, that feels nice... But still un... Hand me? Err, unmist me, whatever the hell the right term is!" she huffed, failing to even register for the moment that she didn't even care about being naked.

Instead of complying, the lamp proceeded to begin altering her mind. It was surprised to discover she was a Goddess, albeit an extremely ditzy one. If she had any degree of competence with her own abilities, she might actually be capable of freeing herself from it. Still, her mind resisted in ways normal humans wouldn't. Not because she wanted to, given how good the experience was feeling for her, but out of pure, divine hubris. The lamp ultimately left its mark in her soul despite this, blending her new genie nature seamlessly with her divine nature. She'd come to rethink her pride later, never completely losing it, but learning to take pride in her newfound servitude.

She then gasped as she felt silk forming from the mist around her body, creating a skimpy, exotic, and embarrassingly enough, see through dancer outfit, complete with detached sleeves, poofy pants, a scanty top, and a veil over her lower face, along with arm bands around her wrists, and a collar around her neck, solid gold, and each piece encrusted with a sapphire.

"...okay, this is lovely, and quite luxurious..." she remarked, admiring herself a bit, not even noticing as her legs and feet dissolved into the mist, all of it condensing into a tail, leaving her floating within the lamp.

She blinked, taking in her new surroundings, which consisted of an absolutely luxurious looking bedroom, and she squeed, not even bothering to question the new knowledge her mind was full of, she'd sift through it later! "Oh, this is heavenly! Wait, where's the exit!?" she then panicked, realizing she didn't see a door anywhere. Sure, the room was nice, but she didn't want to be stuck in here forever! "Kazuma, Darkness, get me out of here already!" she wailed.

...

As if on cue, outside of the lamp, Darkness picked up the lamp and blue smoke once again surrounded them but then Aqua was back, but in a silk see through dancer outfit. And her legs were gone, replaced by a shimmering, misty tail, firmly attached to the spout of the lamp. Aqua looked down, and immediately started tugging on the tail with a shriek, finally noticing what became of her legs, but it wouldn't come loose, or even budge the lamp. "Kazuma! Mistress! Get me out of this!"