[1] The title track served as theme song for the NHK drama series Hatsukoi, starring Yoshino Kimura.

[2] "Koi wa Owaranai Zutto" is Misia's first single in over a year and first since the release of her tenth studio album, Soul Quest.

The first pressing of the physical release includes a poetry anthology written by Misia on the theme of "first love", titled Hatsukoi Uta (はつ恋歌).

[3] Along with the title track, the single features the B-side "Hyakunen Ai", co-written by essayist Mayumi Satō, a stripped-down, acoustic piano version of "Koi wa Owaranai Zutto" and a remixed version of Misia's Japanese-language rendition of "Ribbon in the Sky" by Stevie Wonder, from the cover album Misia no Mori: Forest Covers.

[3] A digital exclusive version, dubbed the Deluxe Edition, including an additional remix of "Koi wa Owaranai Zutto", was released a week later, on June 27, 2012.

[2] "Koi wa Owaranai Zutto" was praised as "authentic" by CDJournal critics, and compared to "Everything" for the analogous vocal restraint shown by Misia.

[8] The music video for "Koi wa Owaranai Zutto" was filmed in May 2012 in Hokkaido and was directed by Mitsuo Shindō.

The video was filmed at several locations throughout Hokkaido, including Lake Cimi-ke-p (チミケップ湖) in the town of Tsubetsu, where the album cover for Misia's EP The Glory Day was photographed, the Pierson Memorial Museum (ピアソン記念館), in the city of Kitami, and the surroundings of Notoro Point Lighthouse (能取岬灯台), in Abashiri city.

The video ends with a shot of Misia resting her chin on her hand and staring out of the same train window as her name and the title of the song appear in white font.

[11] "Koi wa Owaranai Zutto" debuted at number 17 on the weekly Oricon Singles Chart,[12] with 5,000 copies sold.