Actor Daniel Choi and f(x) Sulli were caught on camera together.

Their picture was tweeted by the official Twitter of the play "His and Her Thursday" with a caption that read: "Three special guests visited us to cheer on Park Chul Min today! Awesome Daniel Choi, pretty Sulli, and good-looking Lee Yi Kyung - thank you for the encouragement!"

The picture consisted of Park Chul Min, Lee Yi Kyung, Sulli, and Daniel Choi bundled up together like a family.

The fans responded with comments such as "Daniel Choi and Sully is a great couple" and "Choiza might get jealous of Daniel Choi".