BTS' Jin, Red Velvet's Wendy perform collab song 'Heart on the Window' live

Jin and Wendy shared the stage for a performance the first time ever!

The BTS and Red Velvet vocalists performed their collaboration song "Heart on the Window" live in Seoul, South Korea during Day 2 of Jin's "Happy" Special Stage held on Sunday.

The unexpected treat thrilled fans, and the two singers were praised for their live vocal prowess.

After their performance, Jin vowed to help Wendy if she would ever need anything in the future, and Wendy said she'll be sure to reach out to him first.

"Heart on the Window" is a track on Jin's debut solo album, " Happy ," which was released on November 15. Jin released the music video for the lead track "Running Wild" on the same day.

In October, he dropped the pre-release track " I'll Be There ."

Jin released his debut solo single " The Astronaut " in 2022 before enlisting for the South Korean military.

He was discharged on June 12.

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