Prime number ~Kimi to Deaeru Hi~ (Prime number～君と出会える日～)

“Prime number ~Kimi to Deaeru Hi~” is the second ending theme for Sakura-sou no Pet na Kanojo (The Pet Girl of Sakurasou), the 2012 anime produced by J.C.Staff. Performed by ASCA, the song was released as a single on November 7, 2012.

Written and composed by ASCA, the track uses a pop-rock-leaning J-Pop style typical of anime theme songs. Its role as the series’ second ending theme places it within the show’s original 2012 broadcast, while the single gave it a separate commercial release beyond the anime.