Blithering idiot
01
完全なばか, とんま
a person who is extremely foolish or incompetent
Informal
例
After forgetting his keys for the third time this week, his frustrated roommate called him a blithering idiot.
今週3回目に鍵を忘れた後、彼のイライラしたルームメイトは彼を完全なばか者と呼んだ。
