^ OMG my heart literally skipped a beat when I saw that! Thanks!
I'm pretty sure that's Yukirin's revenge on Mayuyu for all that sexy teasing as they left the stage. I can just imagine Yukirin thinking: I'm going to show you who's boss
Anyway, I rewatched the Request Hour 2013 Day 2 closing scene countless times to capture these images and whatever LOL stuff Mayuyu and Sasshi were spouting about sexy Yukirin
Enjoy!
Yuki vs Pervy MayuSasshi Team Sasshi: Yukirin, that dress is amazing.
Mayuyu: Yukirin sexy o~
Yukirin: *embarrassed laugh*
Sasshi: Sexy... Kawaii o~
Mayuyu: Yukirin is shortcake~
Yukirin: *mumbles* Thank you... thank you...
Sasshi: Shortcake kawaii o~
Mayuyu: Kawaii o!
Yukirin: (n///n)
Conclusion: Mayuyu thinks Yukirin is a sexy shortcake (and probably can't wait to eat her).