dark-natured; gloomy; dour; moody; insular; glum; pessimistic
innate cheerfulness
根暗な性格を直したいと思っている。
I want to fix my gloomy personality.
彼は根暗に見えるが実は面白い人だ。
He looks gloomy but is actually an interesting person.
根暗だと言われて少し傷ついた。
I was a bit hurt being called gloomy.