na-adjective
selfish; self-centered; egotistical
A direct loanword used as a な-adjective. Carries a slightly modern, casual tone compared to native words like わがまま or 自分勝手.
彼はいつも自分のことしか考えない、本当にセルフィッシュな人だ。
He only ever thinks about himself; he's a really selfish person.
そんなセルフィッシュな態度は友達をなくすよ。
That kind of selfish attitude will cost you your friends.