"Bubble" is the sixth single by Japanese rock band Band-Maid, released in Japan on January 16, 2019, by Crown Stones.

[4] They were originally going to use one of their unreleased songs for the show, but lead guitarist Kanami Tōno "realized that the demo I just happened to be working on at the time was a better fit for the drama.

[6] JaME said that the title track "...mixes slow parts with sudden adrenaline outbursts" and that "We bet you will return to this song over and over again for fuelling[sic] up."

And said that "Smile"'s use of "...acoustic guitar and Saiki's warm vocal" "...creates a soft, cosy atmosphere, which wraps you up like a comfortable blanket, while the other instruments serve as support.

"[2] Marc Bowie of J-Generation called the title track "...a typically melodic pounder" and that it "...features a crunching riff".