This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
睧 combines 目 (eye) with 昏 (dusk, dark), suggesting dimness of sight or darkness. The exact historical development is uncertain.
The eye 目 beside dusk 昏 suggests vision growing dim as evening falls. Picture eyes struggling to see in the fading light.
For コン, imagine a con artist squinting in the dark, trying to see: con -> コン, and the dim light makes it hard to see clearly.