AIBU to think this is an odd thing to say?

Yes they are not dating just chatting online and one meet up so I agree with you he sounds quite full of himself to think it's a relationship. But she sounds happy so I'll say nothing and wait and see

I thought it was just a cheeky chappie reply don’t see anything wrong at all and neither does your friend perhaps you took it out of context and put more to it than was meant
Anyway not yours or our business
Seems innocent enough to me personally I think your idea of what he should have said very stilted and a bit old fashioned

Well, we were asked to say what we think, so that's what I did.
If "I'm not dating your dad" is a one liner, I assume he's not a natural comedian.
I would find it quite strange.

Such a lot of assumptions! They have spoken online and on the phone and had a meet up in the park, your friend thinks it was a joke and is happy.
Why is he deemed to be possessive and cocky? The OP wasn’t even there!

Doesn't strike me as remotely strange. In the fact this man's oneliner strikes me as much more natural than the more stilted response you suggest.

It is the response that lots of people I know would have made as a joky response - and your friend seems to have seen it as a joky response as well.

At this stage I’d have been tempted to say ‘who said we’re dating? One meet up. I’d be on high alert so probably super sensitive to a remark like that. I’d be thinking ‘cocky sod’.

Yes.
She will now be a bit wary of mentioning her dad again...

Thank you for your answers. Yes that comment did close the conversation about her dad. I haven't said anything to her but I think he could be a bit negative and possessive. Hope I'm wrong as she seems really happy

To me, having a chat about everything under the sun is the best way to find out about what makes someone tick, what their values are, how their mind works (or if it does)

It sounds as if he is loathe to talk about much.

I agree with MissAdventure.

I think it's a bit abrupt, not cheeky or funny.

I'd be wary of someone who shut down general conversation.

He probably meant it lightheartedly as in I’m not bothered about your dad, I’m more interested in you!

Spot on Oopsadaisy. She must have been talking too much about her Dad.

Maybe she was talking about her Dad a lot without realising?
Maybe he thought that she was about to invite him round to meet the parent?
If she isn’t bothered about it then why worry?

It was just a joke - nothing ‘odd’ about it. He probably meant to say, ‘I don’t want your Dad to cook for me, I want you to cook for me’