Legal Question in Sexual Harassment in California

Generally no, it is not illegal. However, there are a lot of exceptions. For example if it's not the sender's dick and the sender does not have permission to send it, it is illegal. If there is a workplace relationship between the sender and recipient it is probably sexual harassment, unless it is clearly welcome when received. If either the owner of the dick or the recipient is under 18, it is illegal, and so on.