(slang) stupid, meaningless, and uncool

悪い: bad; inferior

(literally) badness / (by extension) mischief

確固: firm

括弧: parenthesis / 羯鼓, 鞨鼓: a small double-headed drum struck with sticks, used in the gagaku music of Japan / 各戸: each house / 各個: each item / (Tsugaru) mulberry

middle child

Used in ( ).

(music) a small double-headed drum struck with two sticks, used in the gagaku and noh music of Japan

to put in parentheses

(と〜) thinking that […] (with the next clause explaining that the truth is contrary to expectations)