From the moment Jax brought back the three siblings to Fairy Tail, the guild changed noticeably. Erza entered a competition with Mirajane, Natsu calmed down and spent more time with Lisanna, Gray spent more time training since Natsu wasn't bothering him anymore. As for Elfman, the brother of the two Strauss girls, he spent some time training with Gray, trying to control his magic correctly. Overall, a lot happened in the guild.
Following their arrival, Jax offered the new members to stay at the house, housing most of the new members of Fairy Tail.
From that moment on, Jax turned back to his training. He trained in the morning, and in the afternoon, he spent some time with the girls, going on dates. Not surprisingly, travelling across the continent on Snow with a girl was indeed one of the best dates he could offer her. As for the evening, he went to sleep and cuddled with the girls, who now surprisingly had to make space for Mirajane on the bed. The reason she was coming to rest with him was that he had to take responsibility for holding her for so long while they flew on Snow. In his opinion, he was simply too awesome and had attracted her attention.
Of course, Jax wouldn't be the one rejecting her. Their bed went from four to five with Jax, Hisui, Cana, Erza and Mira. However, when the girls all went into bed and wanted to sleep next to him, Jax could only conclude that the mattress didn't have more place with the four girls. Moreover, he could also confirm that he was indeed a lucky man.
The relationship between him and the girls got closer as the guild members could often see them kissing everywhere. The only thing they did not yet do was the last step, as the five of them were still a bit young. Moreover, Jax was the only one who could stop Erza and Mira from fighting everywhere. However, he could also tell that despite their constant glare, they still cared for each other as they never went overboard.
Their competition never stopped and for anything as well. Erza was turning into someone who followed every rules as much as possible while mirajane turned into a small hooligan.
Apart from this, the relationship between Natsu and Lisanna seemed to be improving, especially from the moment Natsu appeared with a supposed dragon egg, and Lisanna decided to help him hatch it. Secretly, Jax had Snow verify wether it was a dragon egg as he had her sniff the egg. As a dragon, she would be supposed to be able to tell wether it was an egg from her kin. In the end, the result was negative which Jax found was unfortunate but dragon's had been extinct for hundred of years and for a dragon egg to still exist would be surprising.
Time continued to flow as in April X778, Jax finally added the fourth pearl to all of his different magics. It significantly increased his strength as his magic reached the level of the four gods of Ishgar. The reason he could tell he had this strength was that he once saw a god of Ishgar in action, indeed a spectacular and rare show.
From May X778 to December X779, some things happened. The first thing was the ever-increasing relationship between him and the girls. At this point, there wasn't a need to say it as Jax loved the four girls as much as the girls loved him. Their dates went over the entirety of the continent, and they often came close to go over the line, doing what should only be done between husband and wife.
In addition to this, Jax finally found and saved the younger sister of Sorano, Yukino Agria, during a mission. She lived in a poor orphanage where she was often humiliated by the caretakers and the other children. As such, he didn't leave her there but brought her back to Fairy Tail, offering her a place to learn magic and live freely. In the beginning, she was wondering why he helped her. It was only when he mentioned knowing her sister and keeping a lookout for her that she understood and came with him, which made him sweat since it had been easy, way too easy. Seeing this, he decided to protect her and not let her get kidnapped by some bad people.
As for the orphanage, he sent some news to the king of Fiore, who was more than happy to send some people to take a look and deal with it.
For Yukino, as he brought her back to Fairy Tail, she mentioned wanting to learn true magic and not fake magic such as celestial magic as she called it. Jax was more than happy to teach her water magic, magic she was surprisingly good at in exchange for the Libra and Pisces keys, which were in her possession. Finally, in X779, Erza became an S-rank mage of Fairy Tail as she had everything for her, power, respect and love for the guild.
In X780, following the capture of the hero of Rubengard, Jax was sent on an urgent mission of the magic council to go and capture the dark mage Zoldeo. Many things happened on the way, which included destroying over a dozen of dark guilds, much to the job of the magic council. However, in the end, he found his way to his target, beat him up until even the magic council couldn't recognize him with a wanted poster and took the celestial key of Capricorn.
Talking of Zoldeo, it was necessary to mention Grammi, the mother of Brandish U, who had managed to survive an attack from the dark mage. This threat was also everything that Brandish U needed to join Fairy Tail to increase her magic strength and magic control.
In addition to this, that year's S-class exam was won by Cana, who had been training with Jax for a long time. With this, she completed one of her dreams and took her courage to talk with her father, Gildarts, who was surprisingly happy to learn that he had a daughter.