This is Yuki and Mai's theme from Touhou 5: Mystic Square

This sounds solemn. Maybe Yuki and Mai are having a few relationship problems...

Mai: Look, you have got to stop clinging to me! You're slowing me down! Argh, and why do you keep setting my hair on fire?!

Yuki: Why are you such a BITCH all the time??

Mai: TT__TT Why must we fight...?