Masaka - It can't be! (in this context)
Aneki - more directly translates as older sister, but usually said ... I guess respectfully in a yakuza way? I can't explain it too well

I guess I'll add more subtitles, but I don't think other characters should understand lol

Edit:
Is the energetic girl referring to Komari? (Just confirming)
Also, I completely forgot about the tennis person lol.
Unless you were referring to Rush? Cause his the cult leader, and if not, you forgot about him as he offered to shake Komari's hand, which she didn't take due to his lies!