Is always a little odd right?

I just applied for one today and couldn't find my CV, so I asked the head of recruitment for it on IM and subsequently had a small talk convo about how hungover I am. Also wound her up a bit that I needed it for a role at a competitor. We work together and are pretty matey, also I have been here for ages so know everyone very well.

That's where the weird bit comes in.

On IM - 'Fuck, should not have stayed so late in the pub, feel like shit', 'ha, had a few too many myself, urgh it's a nice day, want to go for a wander, got too much shit on though'

On email to the same person in parallel - 'Dear Blah, I would like to express my interest in blah position. I feel that I am well suited, etc'

The false formality of it all is a bit grating.