Nope! They might look like they are, but the Kaibo Flex actually sits right at the opening to your ear canal.
For the best sound experience and to prevent leakage, you need to find the perfect fit for you and not have any gaps between your skin and the headphones. You can try to raise the Flex up to your ears and move the position of the ear hooks around so the transducer sits right outside your ear.
Please make sure there are no gaps between the headphones and your skin for the best audio experience. Here is a picture of how it is properly worn (also fits with glasses!)