Fate: Bonds Beyond Humanity

"Yes, this isn't good." Rias didn't hesitate in letting Shirou's close.

They came from the tunnels, hundreds of thousands entering from each side. Rats, rats everywhere of many colors and different sizes. The whole rat population of Fuyuki had gathered together and they were out for blood.

"He controls rats…" Rias mumbled but there was no time.

"ATTACK!" With that command the rats advanced.

Rias didn't waste any time and started to throw energy at the rats but they came from all directions. 'Come on, come on!" Rias was in a frenzy trying to take out as many as she could when a group was rushing to the side.

"LOOK OUT!" But Shirou jumped in and started to hit the rats with his wooden sword. He was using reinforcement but focusing on keeping the sword intact, there was no need to strengthen it and he kept his focus on speed instead of power until Rias launched a blast of destruction to his side. "Thanks!"

"FOCUS!" She was glad he helped but the problem was still in the thousands with more and more coming. She kept attacking and attacking but there were too many rats, Shirou was watching her back and getting any rat that was getting too close, she was planning to keep going until the numbers were manageable.

"RIAS! NORTH NOW!" Shirou called and she saw something that clicked the pieces on her brain, giant rats bigger than cars.

"SHIROU! GRAB MY BACK!" They needed to retreat. For a moment he looked confused "JUST DO IT!" The boy placed his arms around her necks and she unfolded her wings.

Aiming for the tunnel with most rats she charged. "YOU ARE NOT ESCAPING!" Another barrier showed up on that entrance but that was the plan, she turned and went faster to a tunnel on the side with fewer rats and unleashed her power on her hands to kill those there. "AFTER THEM!"

"KEEP GOING!" Shirou didn't need to tell her that but he let go with the arm that had the sword. "TRACE ON!" Then he started to supercharge the wood with mana.

Once he felt it was enough he threw it up, hitting the roof the tunnel started to go down from the impact breaking the stone and isolating them from the rats.

Rias kept going, stopping was too risky and now she really wished to have called for help. This was not a fight she can win alone, if she had her peerage then they could win easily… not. That was not an opponent that she could beat like that.

She lands but almost falls if Shirou hadn't grabbed her from her waist. "Are you okay?"

"Just... tired… not used… to fly with extra weight." She takes time to breathe only to notice the stench. "This is…" Please let it not be what she thinks it is.

"The sewer." But it was.

"Damn it." They pass a small whole and enter the sewer proper. "He is going to be chasing us."

"You know who he is?" At Shirou's question Rias lets out a sigh.

"Ever heard of the 'Hamelin's Flutist'?" That surprised Shirou.

"Is that guy-"

"No! But he was once a famous devil that had the skill to control rats, he used it to have hundreds of familiars in his Rating Games."

"'Rating Games'?" Rias covers her face with her hands.

"That is a lot to explain but it is where devils compete for prestige." Rias tries to make a magic circle but it fails. "He is blocking communications somehow."

"I suppose that makes this a boundary field. No sign here." Shirou's cell had no bars. "To be fair we are in a sewer now."

"Or he has the field covering that too." The frustration was apparent in her voice.

"Is he famous in these games?" Shirou starts walking, going to look for an alternative exit. Rias didn't move for a bit and Shirou stopped for her.

After using her magic for a bit she sighs and starts walking as well. "He was good ten years ago. Those that knew the story of the original gave him the name of 'Hamelin's Flutist' as an epithet and that boosted the fame for both him and his King's peerage. He was the strategist and an exceptional one at that, using his familiars, the terrain and barrier magic to great effect. He conquered win after win to the point he was considerably famous."

"So… what went wrong?"

"They lost… a higher class peerage beat them and that was the end of the myth." Rias then touches Shirou's shoulder, having him flinch. "You are hurt."

"Not really." He tried to move the arm but it was stiff. "I reinforced my muscles a bit too much but it was the best way to get us away." They get back to walking. "So they just lost and what? The guy flips?"

"Unfortunately that wasn't their only defeat, it just… all started to go downhill for them." Rias tries to remember but she fails. "I was just a child and don't remember all the details but he killed his king and then he was gone… I think." Rias checks out a corner and they both proceed. "He was a normal human, a magician, before becoming a devil. Without a sacred gear, either he needed to adapt or get left behind."

That was the truth about most competitions, there are adaptations and new techniques that get discovered. For a time or in the lowest tiers manipulating familiars can be devastating but the higher one goes the harder it is for the same tricks to work and rats are also not the strongest of familiars.

"If we had an open space I could end him easily." Rias decided.

"Could you?" Shirou had his doubts. "He managed to stop your strongest attack."

"Yes, but that makes no sense. The Power of Destruction may not be absolute but it makes no sense why it didn't work." Rias was frustrated and it showed. "I can even destroy energy, and I am sure I broke the barrier."