TAKOBOTO

While 〜 To take advantage of a moment of time to do something　(there is an element of cunning in its meaning)
(1)kare ga ｙudan shiteiru suki ni kishuu shite hoshin da zo. The best thing to do is to attack him when his guard is down.
時間に少し開いている隙間を最高の機会とし、そのチャンスを逃さないうちにずるかしこい行為をする。

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みなさん、ジョンさんがいないすきに、をととのえましょう。

Lets prepare the surprise party for John in his absence.

みんながまえをむいているすきにぎゅっとてをひいてほしいんだ。

I want you to take me by the hand while everyone else is looking the other way.

せんせいがよそみをしているすきに、ラブレターをきみがわたしてくれたんだな。

While the teacher's attention was momentarily distracted you passed me a love letter didn't you.

かのじょはきがつかないすきに、かのじょにキスした。

While she didn't pay attention, I kissed her

Is this the same "suki" as in "sukiari", like when someone drops their guard and you grab them?

Tensigh