We're in the way here — they want to have a private chat.
Tips
usage
Two senses: (1) physically ugly/cluttered — "an eyesore"; (2) unwelcome presence — "a third wheel; in the way." The second sense is the more colloquial one. Literal breakdown is transparent: 碍 (obstruct) + 眼 (eye) = "obstructs the eye."
memory
碍眼 = 碍 "obstruct" + 眼 "eye." Anything that physically blocks your view, or any third party blocking a romantic moment, is 碍眼.