Himitsu no Door kara Ai ni Kite (秘密の扉から会いにきて)

"Himitsu no Door kara Ai ni Kite" (秘密の扉から会いにきて) is performed by Yukari Tamura and serves as the first opening theme for the 2014 TV anime Nourin, also known as No-Rin (のうりん), produced by SILVER LINK. It was released in Japan on February 5, 2014 as Tamura's 24th single. Yukari Tamura wrote the lyrics, Yasunori Fujita composed the music, and Akiyuki Tateyama arranged the track.

The song is a bright J-Pop theme driven by quick, buoyant momentum and a polished pop sheen. Tamura's vocal shifts from a light, playful touch in the verses to a more open and hook-focused chorus, giving the melody a teasing lift. Its sound stays crisp and energetic rather than dramatic, which keeps the opening moving with ease.

That upbeat approach fits Nourin's blend of school comedy, idol fantasy, and romantic awkwardness. The single also includes the B-side "Iko yo! Monorail" (いこうよ!モノレール). Commercially, it peaked at number 9 on Oricon's weekly singles chart and reached number 10 on the Billboard Japan Hot 100.