Katson sinuun ylöspäin.

[pitti42]

English Translation

I look up to you.

I thought the illative was weird. Wiktionary does not mention that “katsoa” takes the illative.
So why is it “sinuun”? I asked the natives, and this is what they said:

The illative is triggered by “päin”.
The sentence only has a literal meaning. No admiring.

[hooetvee]

Even with literal meaning, that sounds really weird. Perhaps it’s because… how is that done? Looking at above your head? A literal translation would be ‘Katson sinua ylöspäin’, and I could imagine someone saying it as a joke, but otherwise this doesn’t really make sense.