に居るの

be in/at; be in/at (with の adding an explanatory or casual question nuance)

→ に

phrase Very common #739

be in/at; be in/at (with の adding an explanatory or casual question nuance) の often makes this an explanatory or casual question; the tense depends on the verb form, as in に居たの (were in/at).

JA: 図書館に居るの？

EN: Are you at the library?

あの人たちが、そこに居るの？

Are those people there?

皆は何処に居るの？

Where is everyone?

— ラスト、コーション (2007)

奴ら、中に居るの？

Are they inside?

今キースリング・カフェに居るの

I'm at Kiesling Café right now.

— ラスト、コーション (2007)

そして、カークはどこに居るのだ？

And where is Kirk?

— スター・トレックII カーンの逆襲 (1982)

私よママの故郷の村に居るの

I'm in the village where my mom grew up.

— 灼熱の魂 (2010)