TOP 2 Lee Kwang-soo – Lee Sun-bin
Rado and Yoon Bomi get married in May 2026 (2017 ~ 2026)
Shin Min-ah and Kim Woo-bin married in December 2025 (2015 ~ 2025)
TOP 1 Jeong Kyung-ho-Sooyoung
For reference, actress Oh Na-ra and musical actor Kim Do-hoon are a 26-year-old couple who have been dating since 2000, so it can be considered a common-law marriage.