Here at least, the girls of the Cosplay Cafe band are rehearsing a love song, Aika in the piano, Misato in the drums, Mika in the guitar and voice and finally Kaoru in the bass fiddle. It only remains a riddle to solve, what love song are rehearsing the girls? if you watch with detail, the scene itself will tell you what song is. "In other words" the walls are telling you what song is it. If yo can't find the song's title I'll give you the answer in the next render. EDIT: (some hours later) My friend Raages catch the song's title at the first try, then have the pic's credits hidden for more time has not sense. Shoes by Amy Aimei & Willmap, Keyboard and drums by Rick Bridenbaker at ShareCG, Drum sticks by Music2u4u at ShareCG, Guitar by Zippo, Bass by BardCoennius at vanishing point, piano bench by mjc26250 at ShareCG, Maid and Cop uniforms by Isop, Schoolgirl uniform by Red Viper, Bunny outfit by Amari Jun at vectorized nature, wall stucco texture by hhh316 at DA, Poster frames by Klown (here at Rendo) and myself, Comic book (used as Music sheet) from sweethome 3D, (scaled and retextured by myself), Scenario by myself. images used in the frames: Fly Me To The Moon by Andreas and 60 años del Ken Najshon by Tamara Campos, both on Wikimedia and licensed under the Creative Commons Attribution-Share Alike 4.0 International.