(Crossover) What Should I Do, I'm Good for Nothing?

This time, it is truly an adventure with Jinako and Karna.

"Wait, why do I have to go on an adventure?! Jinako finally worked up the courage to leave her NEET life behind and get a job! If I don't get back soon, I'll definitely get fired!"

"Then we should focus on finding a way back. Stamping your feet won't help, Master."

"Oh, shut up! You too! Learn some tact before you open your mouth, Karna!"

And so, a completely useless Master and her heroic, dazzling Servant set off on a journey.

What could the legendary hero [human] and the self-degrading lump of flesh [human] possibly find at the end of such a journey?

P.S. After the blurb was finalized:

[Jinako: ...Who's a lump of flesh?! Who are you calling a lump of flesh?! I've gotten so much slimmer!]

[Karna: The average weight of Japanese women is sixty-five kilograms.]

[Jinako: ...Please shut up, little... little... bro?]

[Karna: ...]

Notes:

1. Karna and Jinako are from the Type-Moon game Fate/EXTRA CCC. Any OOC behavior is my doing.

2. Jinako's backstory is that her soul travels back into her own past from the future. The rest is still just an idea.

3. I'm not a stickler for canon, and my knowledge of Fate is pretty superficial. Please don't tear me apart.

4. If you've made it this far without closing the page and leaving, thank you for bearing with me. Come brainstorm with me, w!

5. I'm doing a major revision soon, so the story will be locked. If you're willing to wait, thank you so much! Let us Arctic Circle fans make our own content! [Shoo