The two of them have great chemistry doing dialogue-style cross-talk.
Tips
usage
Three common senses to keep apart: (1) job-fit - 专业对口 (your job matches your major) is huge in Chinese career talk; (2) performance-pair - 对口相声 is the two-person form of 相声 cross-talk comedy; (3) palate-fit - 这道菜很对口 means 'this dish suits my taste'.
memory
对 = 'matched' + 口 = 'mouth / opening'. The two openings line up - whether two mouths trading lines, or a slot lining up with the right peg.