BTOB's Eunkwang visited Sungjae during a break from his military service. On January 3, Sungjae shared photos of Eunkwang's visit to his commercial filming on Instagram.

Sungjae posted the photos below with the messages, "Eunkwang hyung who's more dependable now somehow," and "Seo Eunkwang-nim who came to visit me on the set of a commercial filming." In the video clip, Sungjae tells Eunkwang to stay healthy and wishes him a good new year, and Eunkwang responds he'll defend the country well and also said words of encouragement to Sungjae.

Eunkwang will be officially discharged from his military service in May of 2020.