Set after the Alvarez Empire Arc.
Two years ago Lucy went on a one year training mission to search for Aquarius' key. While on her training mission she unfortunately didn't find her key. That year was not waisted Lucy got stronger than any would have ever thought possible. Every town she went to she collected as many different keys she could and now has 84 units. She trained every moment she could and is now able to keep three spirits in the human realm for nearly three hours. When she returned from her what she considered failed expedition she took jobs as many jobs as possible. The further she had to travel the better. Every town she stoped at she asked around for any information no matter if they where rumours or facts any information was good information. Until one day while working a job with team Natsu in the country Monixcies they court wind of a rumour that there was a gold key at the bottom of the deepest lake in the kingdom. They were only ten or so minutes away from Lake Perpetuus. When Lucy heard this she dropped everything. Literally she had a strawberry milkshake in her hand her favourite drink in the entire would and she dropped it. She started sprinting in the direction of Lake Perpetuus followed by the rest of her team. Erza the most physically able person on team Natsu wasn't even able to keep up with Lucy. Not one of them had ever seen Lucy run like this before in her life. She was running at a speed that would make Jet jealous.
I reach the edge of the lake and sure enough there was a shining gold key at the very bottom. The rest of my team arrived behind me a couple of minutes later. Despite being in the coldest part in the coldest country I was to ever whelmed by joy to see Aquarius' key again. I didn't care what Natsu and Gray saw I began stripping down to my undergarments and dove in the water. The water was colder than any ice Gray has ever produced. But that didn't stop me, the water burnt dew to how cold it was and it felt like it was crushing dew to how deep I was going. Nothing is going to stop me from getting Aquarius' key. Until I blacked out barely half way down. The next thing I remember was waking up to Natsu being right in my face.
'what the were you thinking Lucy!' Natsu shouted.
'Yes Lucy you had us all worried,' Erza said lecturing me.
'I was thinking about Aquarius!' I shouted back.
'Lucy you cant be so reckless, you almost died trying to get her key. You need to think about what you're doing,' Gray said
'You're lucky we managed to get to you in time and Wendy was here to heal you,' Carla said disciplining me.
'Open gate of the Air-Pump! Antlia! Is it possible for you to create some sort of oxygen mask for me Antlia,' I asked the gremlin like spirit. Antlia nodded at me and proceeded to cast the spell on me, and I took on my Aquarius star dress incase it helps with being underwater some how; I've never really tested it. The deep crushing pain of the pressure from the water wis still just as bad but at least I didn't feel like my lung were about to explode. The water was as clear as crystal allowing me to see. I reached the bottom and grabbed her key and began my assent back to air. Words cannot describe how joyous I was in that moment. After being separated for three years we would finally be able to see each other again. The fresh pop of stinging Monixcies air. I didn't care about Natsu's slightly perverted smirk, or that Wendy felt insecure about her breast size comparing hers to mine. The only thing I cared about was making a contract with Aquarius again.
I couldn't wait to reach dry land 'I call upon thee, in the world of Celestial Spirits, I recon you to my side at once, pass through the gate. Open gate of the Water Bearer! Aquarius!' In a golden light and a large splashing wave Aquarius appeared.
'Still looks like I'm contracted to a winy brat like you,' Aquarius lectured me.
With tears of joy rolling down my eyes I responded 'I missed you to Aquarius.'