二人っきり

just the two of us

→ 2人
phrase Rare #33,735
just the two of us Means being alone together with only two people, often the speaker and the listener or another person. The っきり ending emphasizes “only” or “just.”
JA: 今日は二人っきりで映画を見よう。
EN: Let's watch a movie, just the two of us, today.

あなたは昨晩私が彼女と二人っきりでいるところを見つけて驚いたにちがいない

You must have been surprised to find me alone with her last night.

二人っきり話したい

I’d like to talk with you alone.

ポルコお話聞かせて今度二人っきりの時に

Porco, tell me the story next time when it’s just the two of us.

— 紅の豚 (1992)

やっと二人っきりなれた

We're finally alone together.