RedHotPie's Messenger system allows you to send photo from your phone's photo library or via your camera. When you choose or take an image to send to someone in Messenger, a copy of that image will be stored in your Shared Album where you can select images to send to people on RHP, rather than going back to your phone's photo library. This way, you can store any intimate images in your Shared Album rather than your phone.
If you send a photo from your Shared Album via Messenger, you can either opt to delete the photo from a particular Conversation or ALL Conversations where you've sent that specific image. To delete the image from a particular Conversation, you just need to delete it as with any image or conversation. To ensure that the image is removed from ALL Conversations, then you need to delete the image from the Shared Album.
Furthermore, any photo sent via Messenger will be removed from all Conversations within 3 months from the date it was sent. You can also now opt to set a photo to be deleted in an hour's time, or a week's time, or a month's time, from the point when you send it. If a photo has been deleted due to it reaching its expiry date, the recipient will be advised that the photo has expired.