Hey, I've come across a sentence: 'I've seen her be a little too into her looks'. I know it means that she cares too much about how she looks.

What else can one be too into?

Can I say:
'He's a little too into money/what other people think'?

Question

Hey, I've come across a sentence: 'I've seen her be a little too into her looks'. I know it means that she cares too much about how she looks.

What else can one be too into?

Can I say: 
'He's a little too into money/what other people think'?

Answer

We can say it in the opposite way: I'm  not really into football(for example). That means I’m not really interested in it.

Answer

Your sentences are correct.
You could also say:
He is fixated on money.
She is very vain.

Answer

Basically to be “into” something means to be interested in it…. A person can be into art, rap music, motorbikes or anything else. 🤓