I think that the whole process should include like 15mins of
foreplay, and 30 to 45mins of intercourse and finally mayb 10 to
15mins of cuddling. For me, longest was 1hr 30mins of intercourse,
but the feel wasn't as great as between 30 to 45mins. Will be abit
sore if continue non-stop for too long, then the feeling will be
less sensitive to be enjoyable.