Does anyone know best Med or method for occasional longer sex...

Hi Me and my 6 years gf has great sex relationship. After 6 years togather we still engage in sex for atleast 10+ times a week of proper session. Few Quickes are extra (Not a big fan of quickie). In terms of bodies and duration of sex we are pretty average. 20-30 min of foreplay and 5-7 min of PIV. I can extend PIV time by being tactful (switching, pausing changing pace and positions).

The thing is sometimes we are in certain position or mood that we would like to go keep going for long at the same pace. Stopping is off putting for both of us. Or at certain occasions or events we would like to have longer PIV sessions. I have suggested Meds for longer stamina few times but she refuses. Main reason is she is not a fan of Meds (even for me) and says that they are mostly anti depressants(which is true).

The help i needed is, Does anyone knows something which will help us have a longer PIV session once a month or once in few months.

We are not looking for a medicine to take regularly but occasionally. Once in month or 2 months. We will love if there is something with no side effects.

A natural herb or something? Or a natural formula.

I have heard about sprays but we are reluctant to use without knowing side effects. If any one knows any please tell us.

Is there anyother risk free way to have an occasional longie?

Thanks for help.