The idiom "necessary evil" refers to an action that is morally wrong or undesirable, but is necessary for achieving a greater good or preventing a worse outcome. It suggests that the action itself is not inherently right, but it is justified by its results.

The idiom "in the good books" means to be considered in a favorable or positive light by someone, usually an authority figure or a person of power. It can also refer to being well-liked or respected by one's peers or colleagues.

The idiom "burst the bubble" means to rupture or destroy a happy or pleasant situation, especially one that has been prolonged. It can also mean to expose an unpleasant truth or to ruin someone's reputation or plans.

The idiom "blind alley" refers to a situation or path that leads nowhere or is a dead end. It can also mean a situation that appears promising at first but ultimately leads to disappointment or failure.

The idiom "of course" is used to express that something is obvious or expected. It can be used to indicate agreement, approval, or understanding.