"Urano Metoria!" Lucy Heartfilia of the Fairy Tail guild shouted. Her losing battle against Angel of the dark guild Oracion Seis did a complete 180º turn with the help of Hibiki from the Blue Pegasus guild (who gave the spell to Lucy) and Lucy's own feelings of love towards Celestial Spirits (which caused Angel's Celestial Spirits to refuse to attack Lucy any longer)…
The powerful spell struck Angel with the power of the cosmos. Of course, this being Fairy Tail, there would be no bleeding wounds or other realistic signs of damage. This being Fairy Tail, battle damage was indicated by clothing damage! Various parts of the evil Angel's clothes were torn off, including one of her boots. After being sent flying by Lucy's last attack, the evil woman fell back into the river they were fighting on… with one boot and one bare foot…
Lucy herself was startled by Angel's landing, having been unconscious during the execution of Urano Metoria and only recently having recovered consciousness. "Huh?" was all she managed to say…
"I knew you could do it…" a tired Hibiki thought with a smile…
Lucy looked around, very confused, while Natsu was still suffering from motion sickness from just being on a raft over the shallow river. The dragonslayer tried to talk, to no avail…
Of course, having been beaten around during most of the fight, Lucy's non-bleeding wounds were still aching. "Huh? What is…? What happened?" she said, and then she noticed her wounded comrades. "Hibiki! Happy! …Oh, right! Natsu!" she exclaimed…
Before she could be of any help to them, though, the seemingly defeated Angel literally resurfaced from below the river water, thirsty for Lucy's blood…
"I… won't… lose… Oracion Seis never loses…" Angel declared, as she made her last Celestial Spirit, Caelum, turn into a cannon, aim at Lucy and charge up an energy shot. Poor Lucy's situation right now seemed hopeless. It seemed that, this time, nothing would save poor little weak Lucy from a horrible death… Or would it?
"One woman… one death…" Angel said as the shot that would inevitably kill poor Lucy charged up. She could already taste the victory, she could already imagine Lucy's bloody corpse floating lifelessly on the river water…
Unfortunately for Angel, luck was firmly planted on Lucy's side. A rather peculiar fish happened to be swimming on those waters at the time, a fish with pretty damn good vision to clearly see the legs of both girls (who were up to the waist into the water), and since it was coming from behind Angel, it could clearly see Angel's bare and exposed foot sole, so vulnerable to whatever might touch it… and this fish in question happened to possess four whiskers it could move at will…
Now, I refuse to call an evil female character "beautiful" (especially after what she did to a cutie like Aries-chan, who is very Hinata-like) until she does a heel-face turn (which I'm told Angel did waaaaay later into the story… but at this particular point she was not beautiful). However, for the purposes of this story, we'll say that the fish got very interested in the beautiful-on-the-outside-only Angel's naked foot…
Everything was set. Lucy closed her eyes, screamed and prepared to die… except the shot that was supposed to kill her was never fired. Instead, Lucy suddenly heard a frantic woman laugh. She opened her eyes only to see Angel laughing out loudly for no apparent reason. "What is her problem?" Lucy asked herself…
Below the river's surface, Angel's bare foot was feeling the fish's whiskers playing with her ticklish sole. The fish enjoyed caressing the arch of Angel's soft bare foot with the very tips of its whiskers. After tickling the arch, the fish went for the heel, the tickled villainess laughing nonstop. Not content with just tickling the sole, the fish swam around the evil woman's foot to tickle its other side…
At that moment, Angel lifted her foot off the ground completely. With the toes now exposed, the fish got its tickly whiskers in-between them…
"Nooo-ho-ho-ho-ho! No-ho-ho-hot the-he-he-here!" Angel screamed as she laughed madly. Lucy was still completely dumbfounded at what she was seeing. She was unable to understand why her enemy suddenly started laughing uncontrollably…
Meanwhile the fish happily tickled the pad of Angel's one bare foot. In fact, it decided to use its four whiskers to tickle the entire woman foot at once. The evil woman was overwhelmed by the tickles she felt on her vulnerable and soft bare foot, all the while her magic power was being drained from having Caelum still out and charging its shot…
The tickle torture ended just as angel had run out of magic power, and the satisfied fish just continued on its way. Without any energy left to keep Caelum in the human world, the Celestial Spirit was teleported back to its own world without shooting Lucy. Without any energy left to keep herself standing, Angel started falling backwards…
"My prayer…" Angel thought as she fell down, her hand trying to reach for the sky. "Disappear into the heavens… like an angel…" she continued thinking as she remembered her time as a child slave, watching a bird fly high in the sky from her prison cell. She finally splashed as she fell and disappeared into the river water. "I said heavens, not water!" she yelled comically…
Lucy did her best to reach Natsu's raft on the river's current and save him, only to fall into the rapids with him. Meanwhile, in Oracion Seis's current base of operations… Brain, leader of Oracion Seis, felt another of the markings on his body disappear, sensing Angel's defeat…
"Impossible! Even Angel has fallen?" Brain asked himself in shock, and then he put an angry expression on his face. "Your death won't be in vain!" he declared…
"…I'm not dead" Angel deadpanned as she calmly floated on the river water, somehow having heard Brain even though his hideout was so far away…
But the punishment for this beautiful-on-the-outside-only evil woman was not over yet. A different fish came from the opposite direction, swimming against the river flow, frontally towards Angel's feet…
This fish stopped right in front of Angel's one bare foot and revealed a long tongue. Angel burst into frantic laughter once again as she felt the new fish's long tongue licking her toes…
"Wha-ha-ha-hat do the fish of this river have with my foot?" Angel complained, wiggling her toes in a futile attempt to escape that tickly tongue…
The fish went on to lick the rest of Angel's vulnerable bare sole. She moved her ankle frantically, trying to escape the tickling, but it was futile…
Some hours after the two back-to-back tickle tortures, it was night time and the battle of the allied guilds against Oracion Seis was reaching its climax. Angel had recovered at least enough to get up and walk, though slowly and still feeling some of the pain of Lucy's final attack…
The defeated villainess had to walk on the forest grass with one bare foot, feeling the tickly grass below her unprotected sole. As if tickle torture hadn't been enough punishment already, she stepped with her bare foot on a puddle of some kind of strangely-colored honey that was dripping from a plant…
"Ewww! What is this sticky stuff?" she complained further. "I'll have to hop on one foot from now on!"
And so she decided to move by hopping on her only booted foot, so she wouldn't step on any other nasty stuff with the bare one. This proved to be a wise choice, because an animal had done its necessities nearby and she would have stepped on them with her bare foot if she had kept on walking normally…
Seeing that her new strategy seemingly worked, she started feeling proud and was already planning how she would get revenge on Lucy… only to stumble on irregular terrain with her booted foot. Without the other foot on the ground to recover balance, she fell down a small ledge, landing inside a giant bell-shaped flower…
Luckily for the evil woman, the flower was not carnivore, so at least she wouldn't get digested. Not so luckily, however, the shape of the plant enclosed her almost completely, with only her one bare foot sticking out…
A small animal happened to be passing by. Angel's bare foot sticking out of the giant flower was still drenched in that weird honey-like liquid. That liquid happened to be sweet and also happened to be that animal's favorite treat. The creature started licking the strange honey-like thing from Angel's bare foot, and as you guessed, that tickled her a lot. Her laugh muffled inside the giant bellflower as her ankle and toes moved frantically in a futile attempt to escape the tickly tongue…
The animal left once it finished its meal, but the commotion had attracted some more unwanted attention: members of the Rune Knights that work for the Magic Council!
Or course, the men thought it was strange to see a bare female foot sticking out of a giant flower like that. One of the men briefly tickled the foot, causing the woman inside the flower to laugh frantically again…
"She's still alive!" they concluded. The Rune Knights rescued Angel from inside the giant bellflower, only to arrest her…
Like all other arrested members of Oración Seis (as well as Jellal Fernandez and the redeemed Richard "Hoteye" Buchanan), she was put inside one of the prisoner wagons destined towards the magic jail…
"Well, at least the tickles have finally ended" she thought with relief. "Now I need to escape from here… Too bad this stupid wagon is especially sealed to prevent me from using magic, and a delicate and beautiful lady like me couldn't possibly brute-force it… I know! I'll seduce the guards! Surely they will fall for my charms! Mwa-ha-ha-ha-ha!"
And so, the villainess put her plan into motion. She slowly stuck her one bare foot out of the little window behind the driver and the other guard, trying to be as sensual as possible…
"Stay inside!" one of the guards said to her as he tickled her foot. The tickled villainess had no choice but to pull her foot back in and patiently wait for her comeuppance…
At least this is more or less how I would have liked it to happen. I seriously can't believe Hiro Mashima wasted that perfect opportunity for female foot-tickling in the canon anime and manga, but thankfully we have fanfics for this sort of thing…
…The end.