This was the thing that made me stumble on this technic(locking myself inside of the car to increase atmospheric Co2 levels)... My woman was so romantic and with very high libido when we both were locked in car in a romantic day off watching the sea in front of us... She said she felt all time high(libido) inside of car and very euphoric... She was in such positive mood and she told me that inside of car the world didnt feel dark or hopeless and everything seemed perfect around... And she said as well that she could just reach the point just for kissing me and hugging me inside of car(we were both consuming oxigen in higher rate so co2 was definitely increasing fast...Window condensation was the evidence) I felt amazing as well... As soon as we left car to go to the beach we lost the high... C02 was the real deal... Since then I have tried to replicate high c02 environment and it definitely increases libido and gives you freaking high positive mood.... My woman face was pinky and very bright and lifted... really looked like an expensive face lift the one you pay 5000 euros and is just for stars...She is around 30 years old and doest look old or older ... but we that co2 facelift she looked 19 year old girl... It shaves me some years as well but was dramatic on her.... C02 is only thing I try to "supplement" everyday because the health benefits are quite stunning... It gives you such positive mood like little child in the perfect environment (love peace lack of anxiety and not knowing what is depression)... PS inside of car my gut is so healthy and it proves c02 lowers serotonin that's why don't feel depressed at all inside of car in that conditions... Another thing we were not having sex ! (we are a very decent couple)so that's why lovers emerging from the back seat of a car look so glowing.