Can I be asexual if I have fantasies?
Yes, asexuality is a lack of attraction, not a lack of fantasy. It is entirely possible to have fantasies that you have no desire to engage in yourself, and for asexuals that may include sexual fantasies. In fact, even non-asexuals can have sexual fantasies which they know they would not enjoy in real life – it's one of the things that can make sexuality confusing even for straight people. A 2016  study found that while asexuals are less likely to fantasise than non-asexuals, for those that do there is a large overlap in topics – notably both groups were equally likely to fantasise about BDSM and fetishes.1
That said, the same study  found there are average differences between asexuals and non-asexuals when it comes to sexual fantasy.2 Compared to non-asexuals, asexuals are less likely to have sexual fantasies – and those that do are more likely to agree with "my fantasies do not involve other people" and more likely to report that their fantasies do not involve themselves. Asexuals were also less likely to masturbate – and those that do are less likely to do so for pleasure.
If you find yourself becoming aroused by fantasies or erotica you may be aegosexual. Aegosexuality is a kind of asexuality where a person may experience arousal in response to certain triggers (typically ones that are removed from themselves), but without any sexual attraction – that is, without any desire to engage in sex being attached.
- There were however, some topics that did display a marked difference. Asexuals that fantasised were significantly less likely to fantasise about group sex, public sex, or having an affair.
- Of course, these are only statistical relationships, and should not be used as strong evidence for or against being asexual.
- : Yule, Morag A.; Brotto, Lori A.; Gorzalka, Boris B. (23 November 2016). Sexual Fantasy and Masturbation Among Asexual Individuals: An In-Depth Exploration. Archives of Sexual Behavior. 46 (1): 311–328. doi:10.1007/s10508-016-0870-8.