Men always start with sex in their mind, it's biological, women look for best gene set to ensure good care of descendants
but hey what am I supposed to know after all? I am not a biologist and I do fall in love
on the other hand, women looking for sex are really a myth, they do not exist and if they exist they find it before getting to you (where you is very much everyone)
Both genders do a body scan when meeting which happens automatically and subconsciously. This is to establish whether they are strong and fit and likely to produce healthy offspring. For men one of the signs is a woman's boobs, hips as this can be crucial for child delivery. There was more, cannot remember them all.
Women do a similar thing.
There are women that are looking for sex only, but I think for women this is more of a phase they go through because of whatever, a short-term thing.
Of course there are exceptions to the rule, as always :)