I once did carpooling for two months, but it wasn't a peer, it was a superior.

She had a car accident and broke her right hand..
Since we lived in the same neighborhood, my team leader told me to give her a ride, so I did.
(She lived in Baekseok and I lived in Hwajeong, so I'm not sure why they called it the same neighborhood.)
She was a married woman in her 30s, and since she was pretty and kind, I liked it.
I especially liked the scent of shampoo when her hair was loosely dried in the morning.
But we didn't talk much; since she was in the car,
she mostly just slept. Anyway.
But still, she gave me 50,000 KRW a month (for gas) and even gave me chicken coupons three times..
And towards the end, her husband even bought me a Korean full-course meal.
Just thought I'd share.
The conclusion is that carpooling is great if you have ulterior motives for dating.
But if you don't, the person in the passenger seat just sleeps.