The True Grand Cavalry [Crossover]

After becoming Martha, I knew my most important task was to tame the evil dragon Tarrasque. And I completed that task perfectly.

But after I was summoned as a Heroic Spirit...

#Grand Rider? Me??!#

#Wasn't I supposed to be a four-star?#

Everyone else: ...Before you say that, could you take a look at the dragon behind you?!

Tarrasque: You people are so damn annoying... (Martha punches him into submission)

Martha: Language!

Tarrasque: ... [As quiet as a mouse.jpg]

Everyone else: ... [As quiet as a duck.jpg]

#I, Tarrasque, also known as [REDACTED]-682, the ender of all life, the most powerful Keter-class [REDACTED]... Yes, yes, I'm still Saint Martha's mount.#

Known fact one: Martha's mount is the evil dragon Tarrasque.

Known fact two: Tarrasque is one of the names of [REDACTED]-682.

Known fact three: [REDACTED]-682 is a Keter-class [REDACTED] capable of destroying the world.

Conclusion: Martha is a Grand Rider.

...That checks out to me_(:з"∠)_

Written for Miss Martha, my first non-event Gold Servant to reach NP2 in FGO. I believe you love me.

#The legendary King of Kicking People Away, my life idol, hahaha#

As for the pairing... probably Martha x Tarrasque, as friends (a one-sided, get-beaten-up friendship still counts... right?). As for anything else... emmmm, undecided, though it might also be no pairing.