Essentially, foods that are meant to be taking immediately after sex should be energy giving foods so that the energy loss can be quickly regained. Notable point worthy of taking into consideration is that foods that are taken before sex basically shouldn't be the same as the kind of foods that should be taken after sex.
Foods that you can consume after sex are foods that are rich in carbohydrates, e.g, oat, rice, tapioca, yam etc. Proteineous foods should also be considered as they are meant to repair the worn out tissues due to the exertion caused by the sex exercise, e.g, chicken, beef, fish, beans, eggs, cheese etc.
Other foods that can as well be taken are foods packed with vitamins and minerals such as fruits and vegetables including water.
Finally, foods that can serve this purpose should be complete balanced diet(containing all the six classes of food) that are in the right proportion to support and replenish the lost energy.