i-adjective
hard to dislike; likeable; impossible to hate
Describes a person or thing that has endearing qualities despite flaws; often used for someone who is mischievous but charming.
彼はいたずら好きだけど、憎めない性格だ。
He's a prankster, but he has a likeable personality.
あのキャラクターは失敗ばかりだけど
That character makes mistakes all the time, but has a charm that's hard to dislike.