First time i took a passenger other than other pilots, was in a glider. Other glider pilots will know that you have to be able to demonstrate a quite a high level of skill and experience to be allowed to take a passenger in a glider, compared with flying solo. You need a P1 rating (essentially a series of checks with the CFI), on top of around 100 hours experience and a Silver C award (varies a bit between clubs).
My wife bravely agreed to be my first passenger. It was a beautiful day and we towed to 2000 feet above the Cotswolds. The thermal god was kind and we were soon at 5000 feet with fantastic views. We meandered around (I didn't feel confident enough go far from the field - decided that landing out might well make this our last joint flying experience...)
After about 1/2 hour, she said "we seem to be going round in circles a lot - does it go in straight line as well?"
Landed safely after an hour (both of us felt quite tired) and she admitted to really enjoying the flight - she felt a bit nervous during the approach and landing, but willing to try it again.
That was three years ago, I went on to get the PPL and we now enjoy flying together regularly in a shared 50 year old aircraft out of farm strip 5 miles from our home.
One of the main reasons I went for the PPL was because i had done a lot of gliding on my own and really wanted company. I could see that taking my wife gliding was going to be of limited interest to her, whereas trundling down to Bodmin, staying overnight in Port Isaac and then returning along the south coast via Compton Abbas (a favourite of both of us) as we did last week is enjoyable for both of us. This year we plan to get to the Scilly Isles and maybe France.
I seldom go flying on my own now. I find that having someone to share the experience enhances the enjoyment greatly.