In fact, on this Reddit thread, people shared what was the first thing that sexually attracted them to someone and the responses are definitely worth a read: 

1. 

Believe it or not, their smile and eyes.

2. 

Eyes can say a lot about someone as can a smile. Voice is something too for me. 

3. 

I’m a simple man. Dimples warm my heart.

4. 

(If) we’re talking just sexual attraction, then the booty. 

5. 

Boobs are always nice, but being able to have a good conversation is what sparks my interest.

6.

Intellect. Funny personality.

Then boobs.

7. 

It’s chemistry and some sort of magic that my body understands nearly instantly. Sure, usually our eyes are often first on the detection scene, so shallow as it sounds, the sight, maybe even scent of a girl you’ve just seen, even from a distance can be the most compelling thing, at least until you actually talk. Often your chemistry and attraction transcend talking and you move right past everything to touching. The talking can make or break everything else. Often it makes this impossible attraction stronger, but sometimes makes it less.

Almost any single feature can be attractive, an expression, smile, hair eyes, breasts, legs but I can’t get past that amazing chemistry thing.

8. 

Beards and tattoos. 

9. 

Smile too, but I’ve found myself being super attracted to someone based on their voice alone.

10. 

Deep voice coupled with a bit of an attitude kills me every time.

11. 

For me, it’s how close and exclusive our bond becomes. If I feel like we have something they don’t have with anyone else, even a close friendship, the potential is there for me to become sexually attracted. There are nuances with that, of course.

12.

Tension. If they can be a little cocky but not in the gross way. But they use it in a way to build tension. Ugh.

13. 

Honestly, it’s just chemistry in the air, if that makes sense. Before a girl even speaks a word generally, I can get a vibe. Other than that physically I’d say her face/smile/eyes. But there are extremely attractive girls I’ve seen that don’t give off a vibe as others do.

14. 

Intelligence isn’t necessarily academic – it often takes the form of wit/humor, daily problem solving, being able to put together / fix objects, etc.

Intelligence without arrogance is very attractive.

15. 

For men it’s charisma. The more they’re able to make me laugh or can create funny inside jokes, the more attracted I become to them.

For women, it’s the voice. Something about a woman with an adorable high-pitched voice gets me started. Pair that with a nice laugh, I’m melting. 

16. 

If he’s big, burly, husky, and hairy with a nice beard and a handsome face, I’m interested.

17. 

Smell. Those damn pheromones. 

18. 

Once I see genuine non-motive driven kindness.

19. 

Hair and just general facial features. I’m a sucker for longer hair on guys. 

20. 

Confidence. Ownership over one’s own agency is sexy!

Sometimes all it takes is just that one thing!