actually you can! asexual like any other sexuality refers to sexual attraction, so asexual = no sexual attraction like any other person when our genitals are stimulated it feels good therefore sex can be enjoyable a person can have fulfilling sex even if they aren't attracted to their partner, for example many gay men have successfully impregnated women. not saying that's an ideal situation but obvi you can still have a nice time even if you're stimulated by physical actions only and not looks