This situation is unlikely to result in a successful claim, the law requires that the attention be “unwelcome,” and because you and your supervisor are engaged in a consensual relationship, courts might not consider you to meet the statutory definition of harassment. This would be considered a tangible employment action for sexual harassment claim purposes. You may want to talk to your supervisor or other resources within your department to see what you can do. Many offices are likely to view this behavior as inappropriate for a variety of reasons; perhaps they can remove you from your supervisor’s chain of command.