Re: This is exactly what the internet was designed for
If you are a closeted heterosexual male or lesbian [1] who is trying to pretend to be asexual, and are concerned that mere sight of a reasonably pretty young lady might provoke an uncontrollable response, then yes, don't watch it when other people are around. Otherwise, I really don't see the problem.
[1] Obviously if you are bisexual, you will be invisible and therefore won't need to worry about any of this.