I think Lawyer Ahn Dan-tae is Jun-pyo

Overview

Dan-tae spots Jun-su continuing to act suspiciously. He loses his trust in Jun-su and suffers from the thought of not being able to be friends like they once were. Meanwhile, Jun-su waits for the results of Dan-tae's DNA test convicted that Dan-tae is Jun-pyo. With this, he proposes something to Tae-cheol.