singer
Dean was featured on "Starlight". Taeyeon officially debuted as a solo singer in October 2015 with the extended play
I, which was a commercial success, peaking at number two on South Korea's
Gaon Album Chart and has sold over 140,000 copies in the country. Following the success of
I, Taeyeon released a single for
S.M. Entertainment's digital music platform
SM Station titled "
Rain", which was a number-one hit on South Korea's
Gaon Digital Chart. As her popularity consolidated, S.M. Entertainment announced on June 17, 2016, that Taeyeon's second extended play
Why would be released on June 28. It was also announced that "Starlight" featuring
alternative R&B singer
Dean would be released as the EP's lead single on June 25. "Starlight" is a midtempo 1990s
retro pop and
R&B song which features "bright"
synthesizers in its instrumentation. Meanwhile, a writer from
Special Broadcasting Service wrote that "Starlight" drew influences from R&B and
EDM. The song's lyrics detail a romantic relationship with the lyrics "You are my starlight, shine on my heart / When I’m with you, it feels like I’m dreaming all day / You are my starlight, I get so happy / Your love is like a gift." == Reception ==