Might be a lame typed story, I kinda just went with what was in my mind as I typed. To try to give this it some story behind it. I added them talking in the end because it made more sense at that scene. Sorry if my story sucks. :c

(Damn I typed a bigger story than I though wow...)

A special evil was unleashed onto the land thousands of years ago, and some of the evil took over pokemon who lived in these lands. Some said it was the fault of YVeltal hibernating in deep underground, but no one really knew the truth, it was a story of legend by the elders, but they also believed in the evil deity along with the deity of life, Xerneas and the earth dragon deity, Zygarde.

This is a story about three demon hunters, they're a powerful Fennekin family, a group of demon slayers who went around warding off pokemon that turned evil, or giving local exorcisms to cleanse them, sometimes had to kill, but that was only when other options failed.
Their fire magic was more special than general pokemon of their species. They had the power of "Blue Flare". A fire that extinguished evil, and can also protect fire pokemon from water based attacks, but took a lot of energy to use it. It was an extremely rare power for fire pokemon, more likely dragons learning it than general fire types, yet their family lineage carried it for millenniums, Lana was born with it from her family, and Kin from his own, it's what made them special pokemon. Blue Flare was not to be used for petty battles or to show off. Was strictly to be used for dangerous encounters and emergencies only.
Kin was the leader and father of the group, Lana was his lover and his partner, they went around helping other pokemon fight off evil spirits since their early days. They evolved into Delphoxs' together. Kin proposed to Lana and they became mates. Short time later, Zli was born, and soon was trained in the arts of demon slaying and exorcism as a Fennekin, even though she couldn't hold things in her paws yet til later. She had a sassy attitude, which would sometimes brought the bad out of her, but nothing they couldnt handle as parents. She soon evolved into a Braixen and was provided her own magical stick which enabled her to use more advanced magic her parents awaited to teach her.

As Kli got stronger, her parents got more proud of her becase she wasn't a slow leaner. They had high hopes for her when she became a mighty Delphox one day. One of their most powerful yet tough skills was being able to deal with rain. As a fire pokemon's weakness it was very important if they planned on saving the world without hiding away from water when it rained all the time. On the side then even made special talismans which they sold to other pokemon to keep evil at bay made from their powers, than and doing daily missions together was their source of income. They were travelers to be specific, and the pokemon they offered their services to gave them places to sleep, and food to eat.
Lana surprised Kin with another child, they been so busy helping people that they lost track of time. Kli was happy to be having a little brother in the future also. This was a great time for them.

One day something weird happened, as an earthquake was felt throughout the lands. Lana was out bringing Oran berries from the nearby forest when it was happening........she was returning to her family with them while they stayed in a cave occupied by an Ursaring and Pangaro family, the shake made her lose her footing and fell over dropping the berries. An energy could be seen coming from the mountains afar. Something came out with evil demonic red glowing eyes. It extended it's claw wing and flapping them vigorously creating wind waves to swift through the forest knocking down everything in it's way, her being caught in the. Lana tried to use light screen but that didn't hold long as the power crashed through it, sending her off, body hitting against a boulder. The impact injured her greatly and caused her to go unconscious.

Yveltal was awaken.....It started raining...

Some miles away in a cave, Kin and Kli were enjoying the delights their hosts gave them. They got rid of the evil that lurked in their cave which was causing everyone constant nightmares when they slept. The Pamchams and Teddiursas celebrated. Soon they felt the tremors of the quake and some of the ceiling became dropping stones around them. Kin and Kli felt something wrong suddenly, they said their goodbyes to the Bear family as their went to go to safer places in the cave.
Kin and Kli ran out and realized Lana hasn't came back. They focused their psychic powers and sensed a extremely weak Lana and followed her energy. As they ran, they soon seen something which they heard in legends flying in the air, and destroying everything in its path as it went on it's way. Was it the Deity of destruction Yveltal?!
A boulder was soon seen in their path and they seen something which looks like something was laying against it of fur, and they was losing a lot of blood.

"MOMMA!"
"LANA!!!!"
They both shouted racing to her side. Kin embraced his mate in her arms. She looked unconscious. With little strength left she weakly looked up to them.

"A...greater evil has returned...Yyyvelt..al,.......I couldn't take it on.....take care of our child...my loves....." she said with her last words and died infront of them. Lots of mourning and cries could be heard from the two after that. They regretted not being with her, they always were together, but thought a simple berry forage wouldn't hurt anyone, they were wrong...

The buried Lana in nearby, decorating the area in beads, and special talismans that symbolized her and what she stood for. Kin paid an Aggron crafter to specially carve a fire symbolized tombstone for her dead wife. Buying flowers to decorate them. Lots of Pokemon came and gave and paid their respects to one of the lands fallen heroes. Kin couldn't leave the tombstone alone one sec, he felt alone without his love by his side. Kli didn't know how to make him feel better. He stood by her side for days, without sleeping or eating or moving at all. All Kli could do was sit close to him and hope they could get through this together. The egg Lana left would soon hatch, and this was the worst time of all to bring babies in the world.
The tombstone glowed like fire, representing the spirit of Lana lurking around them. They noticed this and it made Kin even sadder that before, letting out more tears. He spirit stayed enough to keep them company, but it was her time to leave this world to afterlife for pokemon. It parted from them and floated away up in the skies.

Since the beast of Destruction awakened, it's been raining and lightning ever since.....Yveltal would pay for this...somehow...