Physically... nothing. Not in the strict sense. I caution myself when mentioning I am asexual, people have so many misinterpretations around it, but typically it means we look at someone and don't feel attraction to "them". People talk about things like "look at his abs", "I fantasize about him after hours", etc. and that's not what comes to my mind. A good way of explaining it is, list every characteristic that can make you attracted to someone and then subtract all the things that will ever help you in the bedroom. That is asexuality.

However, that doesn't mean absolutely no physical feelings are possible/exist (the "a" in "asexual" exists in the same way as the "homo" in "homosexual", not the "para" in "parasexual") or that someone cannot develop profound mental/emotional feelings around someone. Many asexuals have turn-ons, often something that to an observer would seem completely mundane and which is a mentally ingrained theme mutually exclusive from any person it can be applied to. I feel like the whole atmosphere feels different under some situations as I look to someone. It feels like a total rush, though because of the asexuality, my mind doesn't connect the hypothetical situation to the other person being in a relationship with me.

As for mentally and emotionally, the few people who I might be able to count on are the only things that have any gravitational effect on me. I am drawn to them as they embody my thought processes and give my drift an anchor.