Contracting いる+の to

Grammar: Colloquial and Casual Speech » Contracting 〜いる+の to 〜いんの

In casual speech, いる followed by の may contract to いんの.

Examples

Is something there with いんの

Learn the meaning and usage of the grammar いんの in Japanese, with examples from manga.
名探偵コナン » Volume 9 » Page 11

In a game of hide-and-seek, Conan and Ayumu find they’re hiding on the same bench. Their conversation attracts the seeker, Genta, leading him to find Conan. As Ayumu sneaks away unseen, she signals an apology to Conan.

コナン:
「バカ (はや)(かく)れてろ!」
“Stupid, hurry and hide!”
元太(げんた):
「ん? なんかいんのか?」
“Mm? Is something there?”

Where are you at with いんの

Learn the meaning and usage of the grammar いんの in Japanese, with examples from manga.
orange » Volume 5 » Page 30

Azu is with her friends, waiting for Suwa. They call him to find what’s keeping him, and while Azu talks with Suwa by phone, she hears an echo of his voice in the distance.

あずさ:
須和(すわ)? (いま)どこにいんの?」
“Suwa? Where is it you're at right now?”
須和(すわ):
「じゃあ もう()る」
“Well, I'm hanging up now.”
あずさ:
「えっ」
“Eh?”

Why is it you're here with いんの

Learn the meaning and usage of the grammar いんの in Japanese, with examples from manga.
ひとりぼっちの○○生活 » Volume 1 » Page 107

Aru returns to her classroom after club. Expecting the classroom to be empty, she’s singing a song about herself as she enters the room. There, she finds her friends idling away the time.

アル:
「なな (なん)(みな)いんのよ!((だれ)もいないと(おも)ってた!)」
“Wh- why is it that you all are here?! (I was thinking no one was here!)”
なこ:
「(なんだ(いま)(うた)…)」
“(What was with that song just now...)”
ソトカ:
師匠(ししょう)がアルを()つって」
“Master said she'd wait for you.”
アル:
「でも(わたし)部活(ぶかつ)あるわよ」
“But I'm in a club!”