Leo's Return

Leo's Return is an event that takes place during the Loke arc.

Prologue
Following Loke's desertion of Fairy Tail and her consultation with Crux, Lucy pinpoints Loke's current location: Karen Lilica's grave. Upon finding him, Lucy tells the man that everyone is looking for him before asking if the place he's standing in front of is Karen's grave; Loke is shocked at Lucy's presence. Lucy then states that Karen was Loke's original summoner, correctly deducing his true identity as the Celestial Spirit Leo the Lion.

Loke smiles at Lucy's power of deduction and praises her for being able to discover his greatest secret, to which Lucy replies that she's a Celestial Spirit Mage who has made a plethora of contracts, and that she felt the true Loke, though she adds that she should have known sooner. Explaining that after the contractor dies the spirit is forced to return to the Celestial Spirit World until their next summoner appears, Lucy mentions that if Karen was Loke's summoner and that she's now deceased, Loke should've been forced back into the Celestial Spirit World. Meekly smiling, Loke listens as Lucy states as humans cannot survive in the Celestial Spirit World, the opposite also holds true, and that a spirit's life force slowly drains away until they die if trapped; Loke states that he's been trapped for three years.

Hearing that he's been living in the human world for three years, Lucy incredulously stays that the fact that he's lived past one is a miracle. Loke agrees with Lucy and states that he's finally reaching the end of the line; he's losing the remainder of his will and strength. Lucy demands Loke to tell her why he can't return to the Celestial Spirit World so that she may open the Gate for him. Loke states that he doesn't need her help, and over the top of Lucy's statement that he'll die if he doesn't return, he mentions that the reason he cannot is simple: he broke the sacred bond between summoner and spirit and was therefore exiled for all eternity, surprising Lucy. Loke tells her that he will die for his sin without complaint, as he is a traitorous spirit; he is the one that killed Karen.

Still shocked at this tidbit of information, Lucy repeats Loke's statement in the form of a question; Loke solemnly states that if a spirit kills its summoner, they will die in the human world. Loke then turns around and, staring at Karen's grave, tells Lucy the events that led up to his current predicament. After he finishes Loke smiles and collapses, stating that he's almost out of time, though Lucy screams for him not to say such a thing. Lamenting over what he did, Loke tells Lucy that Karen went out on a job without the ability to summon her spirits and lost her life; he states that he as good as ended her life and that since that day, the Celestial Spirit World has rejected him. With his body slowly disappearing, Loke thanks Lucy for allowing him to meet a Celestial Spirit Mage as kind as her. Panicking, Lucy screams that she'll help Loke, begging him not to give up hope.

Still smiling, Loke asks Lucy to give everyone at Fairy Tail his regards, though Lucy screams that if he returns to the Celestial Spirit World he'll live; Loke says such a thing is impossible. Regardless, Lucy hugs Loke, saying that what happened to Karen was an accident, and repeatedly tries to open his Gate. Saddened by his friend's effort, Loke tells Lucy that it's fine and asks her to stop, though she refuses. Asking Loke how she can let one of her friends disappear right before her, Lucy tries to force Loke's Gate to open, causing her to merge with the Celestial Spirit energy, warranting her Loke's concern; Lucy makes an even greater effort than before, prompting Loke to tell her that if she continues, she'll disappear alongside him. Beginning to cry, Loke shouts for Lucy not to add to his sin; Lucy counters that if the rule of the Celestial Spirit World is to kill those who defy their contracts, then she'll change it, shocking Loke. With that, all time stops and the elements begin to spiral into chaos; Loke, completely at a loss for words, watches as the Celestial Spirit King himself appears before the two.

Leo's Return
Shocked by the King's sudden appearance, Loke questions the reason as to his arrival whilst Lucy simply marvels at him. Staring down at Loke, the King tells Loke that they who bear keys are forbidden from killing their summoners, reminding him that even though he did not directly do it, he was still responsible for Karen's death, meaning that even after all this time he is forbidden from returning to the Celestial Spirit World. Angry, Lucy shouts at the King, calling him unreasonable; Loke pleads for her to stop, but the King tells her that that rule is the only one that he cannot change. Shocked at Lucy's gallantry, Loke realizes that Lucy's declaration was enough to force the King to appear. While questioning the King's reason for showing up for "something so insignificant", Lucy states that Loke has been suffering for 3 years and that what he did was for the sake of Aries. Conflicted, the Celestial Spirit King tells Lucy that the wishes of his old friend pains him, but Lucy counters that old friends don't matter as his current friend is suffering right in front of him. Begging for him to reconsider, Lucy asks the King how he can consider Loke as guilty, as what he did will never be considered wrong in her eyes. Conflicted, Loke screams for Lucy to stop as he doesn't need forgiveness and only wishes to atone for his sin. Releasing a surge of Magic Power, Lucy tells Loke that she won't let him do that and momentarily summons a multitude of her Celestial Spirits, stating that caring for your friends isn't a sin.

Loke, amazed, notes at the amount of summons Lucy just performed; Lucy immediately collapses and her Spirits return to the Celestial Spirit World. Forcing herself up, Lucy tells the King that her friends feel the same as her regarding Loke and Aries, and that as a fellow Celestial Spirit, he should as well. The King looks down at Loke and Lucy and contemplates as the former rushes towards the latter, telling her that she could've died for the stunt she just pulled. The Celestial Spirit King then speaks: he tells them that if Lucy would go so far to save Loke, then perhaps the "rule" is the one at fault, not him. Understanding Loke's situation at last, the King tells him that saving Aries was an act of compassion, not of sin, and allows him to return to the Celestial Spirit World, much to his shock.

Lucy then smiles at the King and, after winking at him, tells him that he has a benevolent smile, prompting the Spirit to smile. Returning the flow of time to normal, the King tells Loke to thank "the guidance of the stars" for his vindication. Beginning to tear up, Loke asks the King to wait; the King tells Loke that if he continues to feel remorse, then he should support another and live on as their Celestial Spirit. The King continues by saying that there is nobility in valor, and that the friends you'd lay your life on the line for are the ones worth standing by.

With time now returned to normal, Lucy turns around and smiles at Loke, telling him that everything went as planned; Loke smiles at her as the tears pour down his face. Behind him, Loke's gate opens and he is readmitted into the Celestial Spirit World. Fading into his rightful home, Loke internally states that although this does not absolve his sin, it has given him the courage to live and move forward. Loke's key appears in Lucy's hand as he completely fades away, stating that he looks forward to being the pillar that supports Lucy; Lucy says the same for him.

Aftermath
Soon after, Loke and Lucy return to the guild, where he informs everyone that he is a Celestial Spirit. Unable to believe Loke, Natsu tells Loke that he looks completely human; Loke tells Natsu that Virgo is human, though he counters by saying she can turn into a less-than human form, which he acknowledges. Lucy then turns around and tells them that Loke is the Lion Celestial Spirit, taking them all by surprise, sans Happy, who begins to fawn over Loke as he is a "full-grown cat". Gray asks Loke if he can return to being a regular guild member, which Loke denies, saying that he is Lucy's Celestial Spirit and will only show up to save her when she is in distress. With that, Loke picks up Lucy, against her will, and walks away with her in his arms, telling her that they must talk about their plans for the future. Though he quickly puts her down, Lucy orders Loke to return to the Spirit World after he makes a remark about Lucy's love for Spirits. Though, before she does, she hands her several tickets for a resort, explaining that he can no longer go there with his "girlfriends". Disappearing, Loke tells them that he already gave one ticket to Erza.